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Sample records for gastrointestinal fractional absorption

  1. Plutonium gastrointestinal absorption by adults baboons

    International Nuclear Information System (INIS)

    Lataillade, G.; Madic, C.; Willemot, J.M.; Germain, P.; Colle, C.; Metivier, H.

    1991-01-01

    Gastrointestinal absorption of plutonium was investigated in baboons after ingestion of plutonium solution (oxidation states III; IV; V; VI), and plutonium incorporated in soya bean and winkles. We studied the effects of oxidation state and ingested mass for masses ranging from 0.35 μg to 51.6 x 10 +3 μg (4 x 10 -2 to 7776 μg of plutonium per kg of body weight). No clear increase in plutonium retention was shown for concentrations of plutonium smaller than 1 μg/kg. From 1 μg/kg to 1 mg/kg no effects of mass or oxidation state was observed and the mean fractional retention value was 10 -4 . For ingested masses higher than 1 mg/kg the fractional retention values respectively increased for Pu(V) and Pu(III) to (0.9 + 0.2) x 10 -2 and (7.4 + 4.1) x 10 -4 of the ingested mass. This increase might be due to the weak hydrolysis of these oxidation states which would increase gastrointestinal absorption by decrease of hydroxide formation. The fraction of plutonium retained after ingestion of soya bean was (3.0 + 0.5) x 10 -4 about 3 fold higher than the value for 238 Pu nitrate solution. No clear increase in plutonium retention was shown after ingestion of winkles containing 238 Pu. In conclusion, except for high masses of ingested Pu, the retention of which could reach 1% of the ingested dose, our results show that the gastrointestinal transfer factor of 10 -4 proposed by ICRP for gastrointestinal absorption of soluble form of Pu is acceptable, but 10 -3 would provide better safety margin [fr

  2. Gastrointestinal absorption of uranium in man

    International Nuclear Information System (INIS)

    Larsen, R.P.; Orlandini, K.A.

    1984-01-01

    A method has been established for determining the fractional absorption of uranium directly in man. Measurements are made of the urinary excretion rates of uranium for individuals whose drinking water has a high 234 U to 238 U activity ratio and is the primary source of 234 U in their diets. For two individuals, the values obtained for the fractional absorption of 234 U were 0.004 and 0.006. The values obtained for the fractional absorption of 238 U, using a literature value for the 238 U intake from food, were 0.008 and 0.015. The present ICRP value is 0.20. 7 references, 1 table

  3. Gastrointestinal absorption of Np in rats

    International Nuclear Information System (INIS)

    Wirth, R.; Volf, V.

    1985-01-01

    The effect of Np mass and the acidity of the administered Np solutions as well as the age, sex and nutritional status of the animals injected or gavaged with 239Np or 237Np were determined. The latter factor proved to be dominant for absorption of Np from the gut. Thus in fasting weanling and young adult male rats, the absorption of 239Np was sixfold higher (0.18% and 0.12%, respectively) than in fed ones (0.03% and 0.02%, respectively). Absorption by fasted adult females was 0.05% of the administered 239Np, about half of that of adult males. Raising the Np-mass gavaged to fasted female rats to 1 and 10 mg 237Np/kg resulted in an absorption of 0.23% and 0.26%, respectively. Thus, an increased absorption of Np in adult rats seems to be expected only if a large mass is ingested. No dependence of the absorption of Np on nitric acid concentration was found. The data obtained after oral administration of 238Pu and 239Np to adult rats suggest that the f1 factor recommended by the ICRP for fractional absorption of soluble Np compounds from the gut should be decreased, whereas the f1 factor for soluble Pu compounds should be raised

  4. Gastrointestinal absorption of neptunium and curium in humans

    International Nuclear Information System (INIS)

    Popplewell, D.S.; Harrison, J.D.; Ham, G.J.

    1991-01-01

    The gastrointestinal absorption of Np and Cm has been determined in five male adult volunteers. The Np and Cm, which were in citrate solution, were taken with food. An initial experiment with each individual determined the fraction of each element excreted in the urine following intravenous administration. Subsequently, the results for urinary excretion for the two routes of administration were used to calculate the fractional absorption (f1) of ingested Np and Cm. The mean f1 values were: Np (2.0 +/- 0.2) X 10 - 4 , range (1.2-2.9) X 10 - 4 , and Cm (1.7 +/- 0.3) X 10 - 4 , range (0.95-3.0) X 10 - 4 , the quoted uncertainties being the standard error of the means. Currently, the International Commission on Radiological Protection recommends a value of 10 - 3 for both elements. Cumulative urinary excretion over 1 wk after intravenous injection accounted for about 20%-40% of administered Np and 7%-10% of Cm. At the conclusion of the experiment, the total committed effective dose equivalent for each volunteer was calculated to be in the range 130-250 microSv, based on the individual f1 values, and, in some cases, a knowledge of the rate of clearance of 239 Np through the gut as measured by whole-body counting

  5. Absorption of 249Bk from the gastrointestinal tract

    International Nuclear Information System (INIS)

    Zalikin, G.A.; Nisimov, P.G.

    1988-01-01

    In experimets with albino mongrel female rats a study was made of the absorption of 249 Bk from the gastrointestinal tract after a single per os administration. The bulk of 249 Bk (96 per cent) administered either intravenously or per os was mainly deposited in the skeleton and liver. The value of 249 Bk absorption from the gastrointestinal trat by days 4 and 8 following administration was 0.05 per cent

  6. Gastrointestinal absorption of soluble uranium from drinking water. Published paper

    International Nuclear Information System (INIS)

    Wrenn, M.E.; Singh, N.P.; Ruth, H.; Burleigh, D.

    1988-04-01

    This manuscript describes results of an experiment to determine the gastrointestinal absorption of uranium from drinking water in 12 health adults. Most of the uranium ingested was excreted in feces in the first 2 days following ingestion of the water. The absorption was the same for (234)U and (238)U for each subject. Absorption varied among subjects from -0.02% to 2.6%, with a mean of 0.6%. Low absorption may be due to concurrent ingestion of food

  7. Gastrointestinal absorption and retention of neptunium by fasted and fed mice

    International Nuclear Information System (INIS)

    Larsen, R.P.; Bhattacharyya, M.H.; Oldham, R.D.; Moretti, E.S.

    1982-01-01

    The retention of neptunium in liver and bone subsequent to its gastrointestinal absorption has been determined in both fasted and fed mice. The values obtained for fractional retention were 3 x 10 - 3 and 1 x 10 - 4 , respectively, and are within a factor of two the same as those for plutonium in fasted and fed mice

  8. Retention of plutonium in the beagle after gastrointestinal absorption

    International Nuclear Information System (INIS)

    Toohey, R.E.; Bhattacharyya, M.H.; Oldham, R.D.; Larsen, R.P.; Moretti, E.S.

    1985-01-01

    A 0.01 M bicarbonate solution containing 130 nCi (approx. 5 kBq) of 237 Pu (90% hexavalent, 93% ultrafilterable) was administered via gelatin capsule to six adult male beagles following a 21-hr fast. The dogs were sacrificed after 5-6 weeks and the percentage of the administered plutonium retained in the liver plus skeleton and its distribution within the skeleton were determined. The mean amount retained in these tissues was (0.063 +- 0.006)% of the administered dose. The mean amounts of plutonium in the liver and the skeleton were approximately equal, and the distribution within the skeleton was similar to that observed by other workers following either intravenous injection or inhalation. The value for plutonium retention by the dog is about a factor of three less than the values the authors have reported for rodents. It is a factor of 7 greater than the product of the values for gastrointestinal absorption (f 1 ) and fractional retention (f 2 ) recommended by the ICRP for man

  9. Gastrointestinal absorption and anti-inflammatory effect of bromelain

    Energy Technology Data Exchange (ETDEWEB)

    Izaka, K.I. Yamada, M.; Kawano, T; Suyama, T [Green Cross Corp., Osaka (Japan). Research Lab.

    1972-08-01

    In intraduodenal administration of /sup 125/I bromelain in the dog, a blood radioactive peak was attained at 4 hr, equivalent to 9.2% of the administered radioactivity, but, over 24 hr after the administration, 0.213 to 0.263% of the dose was found in the high molecular serum fraction, 21% of which was respondible for the absorbed as intact, equivalent to 0.042 to 0.052% of the administered. The gastrointestinal absorption immunologically proved the same. In intragastric administration of enteric-coated capsules containing /sup 125/I-bromelain as much as 1/8 th of the intraduodenal dose, the blood level reached the maximum at 6 hr following a 3 hr lag phase, equivalent to 0.6% of the administered, and 0.013% of the dose was attributed to the radioactivity in the high molecular serum fraction. The presence of bromelain absorbed was not evidenced immunologically. In intravenous administration of /sup 125/I-bromelain, /sup 125/I-bromelain was eliminated from the circulation at 50 min half-life, and low /sup 125/I molecules were detected immediately after the administration; it is indicative of the rapid break-down of /sup 125/I-bromelain by serum proteases. A binding of these low /sup 125/I-molecules to serum proteins was also revealed. A 24 hr urinary collection was found 68% of the dose. As for the anti-inflammatory effect of bromelain on the carrageenin-induced edema in the rat hind paw, bromelain orally administered in enteric-coated form showed 6.6% inhibition of edema at 73.5 mg/kg dose, and 39.0% inhibition at 120 mg/kg dose. This effect highly significant and almost equivalent to that obtained with hydrocortisone given at 10 mg/kg dose, while no powdered bromelain orally administered showed an inhibitory effect on the edema at 20 - 300 mg/kg dose level. The data obtained here indicate that orally administered bromelain is absorbable from the gastrointestinal tract and exhibits fairly potent anti-inflammatory activity on the exudative phases in enteric

  10. In Silico Modeling of Gastrointestinal Drug Absorption: Predictive Performance of Three Physiologically Based Absorption Models.

    Science.gov (United States)

    Sjögren, Erik; Thörn, Helena; Tannergren, Christer

    2016-06-06

    Gastrointestinal (GI) drug absorption is a complex process determined by formulation, physicochemical and biopharmaceutical factors, and GI physiology. Physiologically based in silico absorption models have emerged as a widely used and promising supplement to traditional in vitro assays and preclinical in vivo studies. However, there remains a lack of comparative studies between different models. The aim of this study was to explore the strengths and limitations of the in silico absorption models Simcyp 13.1, GastroPlus 8.0, and GI-Sim 4.1, with respect to their performance in predicting human intestinal drug absorption. This was achieved by adopting an a priori modeling approach and using well-defined input data for 12 drugs associated with incomplete GI absorption and related challenges in predicting the extent of absorption. This approach better mimics the real situation during formulation development where predictive in silico models would be beneficial. Plasma concentration-time profiles for 44 oral drug administrations were calculated by convolution of model-predicted absorption-time profiles and reported pharmacokinetic parameters. Model performance was evaluated by comparing the predicted plasma concentration-time profiles, Cmax, tmax, and exposure (AUC) with observations from clinical studies. The overall prediction accuracies for AUC, given as the absolute average fold error (AAFE) values, were 2.2, 1.6, and 1.3 for Simcyp, GastroPlus, and GI-Sim, respectively. The corresponding AAFE values for Cmax were 2.2, 1.6, and 1.3, respectively, and those for tmax were 1.7, 1.5, and 1.4, respectively. Simcyp was associated with underprediction of AUC and Cmax; the accuracy decreased with decreasing predicted fabs. A tendency for underprediction was also observed for GastroPlus, but there was no correlation with predicted fabs. There were no obvious trends for over- or underprediction for GI-Sim. The models performed similarly in capturing dependencies on dose and

  11. Estimation of uranium GI absorption fractions for children and adults

    International Nuclear Information System (INIS)

    Chen, J.; Lariviere, D.; Timmins, R.; Verdecchia, K.

    2011-01-01

    Uranium is ubiquitously found in drinking water and food. The gastrointestinal tract absorption fraction (f 1 ) is an important parameter in risk assessment of uranium burdens from ingestion. Although absorption of uranium from ingestion has been studied extensively in the past, human data concerning children and adults are still limited. In a previous study based on measurements of uranium concentration in 73 bone-ash samples collected by Health Canada, the absorption fractions for uranium ingestion were determined to be 0.093 ± 0.113 for infants, and 0.050 ± 0.032 for young children ranging from 1 to 7 y of age. To extend the study, a total of 69 bone-ash samples were selected for children and adults ranging from 7 to 25 y of age and residing in the same Canadian community that is known to have an elevated level of uranium in its drinking water supply. For each bone-ash sample, the total uranium concentration was measured by inductively coupled plasma mass spectrometry. To solve uranium transfer in the biokinetic model for uranium given in International Commission of Radiological Protection (ICRP) Publication 69 with estimated daily uranium intake, the program WinSAAM v3.0.1 was used. The absorption fractions were determined to be 0.030 ± 0.022 for children (7-18 y) and 0.021 ± 0.015 for adults (18-25 y). For anyone more than 18 y of age, the estimated f 1 value for uranium agree well with the ICRP recommended value of 0.02. Published by Oxford Univ. Press on behalf of the Canadian Government 2010. (authors)

  12. Continued studies of the gastrointestinal absorption of plutonium by rodents

    International Nuclear Information System (INIS)

    Larsen, R.P.; Bhattacharyya, M.H.; Oldham, R.D.; Moretti, E.S.; Spaletto, M.I.

    1982-01-01

    In the mouse the gastrointestinal absorption of hexavalent plutonium (the form present in chlorinated drinking water) is (1) a factor of about ten lower in the fed animal than in the fasted one (0.015 vs 0.15%), (2) independent of plutonium concentration over a range that broadly brackets the MPC for plutonium in drinking water, and (3) independent of the time of day the solution is administered to fasted animals. Other factors related to the determination of G.I. absorption which have been investigated are: (1) the adsorption of plutonium onto teeth of animals during both gavage and ad libitum administrations, (2) the formation of polymeric tetravalent plutonium during and subsequent to solution preparation, and (3) the relationship between the metabolic behavior of plutonium solutions, administered both intragastrically and intravenously, and their ultrafilterability

  13. Gastrointestinal drug absorption in rats exposed to 60Co γ-radiation

    International Nuclear Information System (INIS)

    Brady, M.E.

    1976-01-01

    Following exposure of the gastrointestinal (GI) tract to ionizing radiation, its structure and function are altered for several days. Such alterations may affect the bioavailability of orally administered drugs. The potential mechanisms by which radiation may affect drug absorption were explored by studying the absorption of four test drugs, sulfanilamide, bretylium, sulfisoxazole acetyl, and riboflavin, in rats that were exposed to 850 R cobalt-60 gamma-radiation or sham irradiated. In one series of experiments, the drugs were administered orally and the amount of drug excreted in urine was used as a measure of the extent of their absorption. Cumulative urinary excretion of the drugs was shown to be a valid measure of absorption since it was not affected by radiation after intravenous administration of the drugs. At one day post-irradiation, the extent of absorption of sulfanilamide and bretylium was not affected by radiation but the absorption of sulfisoxazole acetyl and riboflavin was increased. At five days post-irradiation, there was no detectable difference between irradiated and control animals in the extent of absorption of the drugs. The fraction of sulfanilamide excreted in the urine as 4 N-conjugate was increased at one day post-irradiation. The increased excretion of metabolite appeared to result from metabolism of the drug by gut flora prior to absorption. This study shows that radiation-induced alterations in the absorption of orally administered drugs are due primarily to slowed gastric emptying. In general, slowed gastric emptying causes the rate of drug absorption to decline. The extent of absorption of drugs that are normally well absorbed is not affected by radiation while the extent of absorption of drugs that normally are absorbed poorly may be increased after irradiation of the GI tract

  14. Effects of duration of fast and animal age on the gastrointestinal absorption of plutonium

    International Nuclear Information System (INIS)

    Bhattacharyya, M.H.; Larsen, R.P.; Oldham, R.D.; Moretti, E.S.; Spaletto, M.I.

    1986-01-01

    The fraction of plutonium absorbed after oral administration of Pu(VI) to 24-h-fasted mice was 19 X 10(-4), 13-fold higher than in fed mice, 1.4 X 10(-4). We have investigated the relevance of the high gastrointestinal (GI) absorption value for the 24-h-fasted animals in setting drinking water standards for humans. When fasting was initiated at the beginning of the active phase of the mouse's daily activity cycle (when they would normally eat), plutonium GI absorption rose from 2.8 X 10(-4) at zero-time to a level typical of the 24-h-fasted mouse after only 2 h of fasting. In contrast, in mice allowed to eat for 4 h into their active phase prior to initiation of the fast (meal-fed mice), 8 h of fasting were required before GI absorption rose to a level similar to that of the 24-h-fasted mouse. The fraction of plutonium retained after gavage administration of Pu(VI) to 1-day-old rats was 74 X 10(-4), 70-fold higher than the value for fed adults. Retention after GI absorption in neonates remained 30- to 70-fold higher than in adults until weaning. One week after weaning, the fraction absorbed and retained by fed weanling rats was the same as that for fed adults, 1 X 10(-4). Drinking water standards for plutonium have been set based on GI absorption values for fed adult animals. The 10- to 100-fold increases in plutonium absorption in young and fasted animals reported by ourselves and others, and the rapid rise to fasted levels of absorption at the start of the animal's active phase, indicate that consideration should be given to elevated levels of plutonium absorption in young and fasted individuals

  15. Gastrointestinal absorption of soluble uranium from drinking water by man

    International Nuclear Information System (INIS)

    Wrenn, M.E.; Singh, N.P.; Ruth, H.; Rallison, M.L.; Burleigh, D.P.

    1989-01-01

    The gastrointestinal absorption of uranium has been measured in ten normal healthy adult volunteers of both sexes by feeding them one litre of water containing 200 to 300 μg of uranium per litre. The water was consumed during normal daytime activities while food was also ingested at its normal rate. Complete collections of urine and faeces were made and compounded on a daily basis over a period of two weeks, one week being prior to the consumption of the uranium-containing water. Uranium was measured by radiochemical separation followed by alpha spectrometry. Both 234 U and 238 U were determined. The results on these people showed that the uptake of uranium under these conditions averaged 0.6%, well below the f 1 of 5% assumed by the ICRP. (author)

  16. Gastrointestinal absorption of plutonium by the Marshall Islanders

    International Nuclear Information System (INIS)

    Sun, L.C.; Meinhold, C.B.

    1997-01-01

    The gastrointestinal absorption constant (f 1 ) is a critical parameter in assessing systemic uptake following the ingestion of a radioactive material and in monitoring such intakes. This study addresses the latter, particularly, for plutonium. and from environmental measurements derives an f 1 value of 4 x 10 -4 for the Marshallese population. The uncertainty associated with the methodology and measurements used in this f 1 value assessment is evaluated. This evaluation takes into account the results from 24-h urine samples and the particular lifestyle of the Marshallese. Plutonium intake resulting from soil consumption is a primary parameter in this evaluation; for this study, it was assumed to be 500 mg d -1 . The f 1 , value determined here is consistent with the values in ICRP Publication 67 of 5 x 10 -4 for ages 1 to adult, and is the same as that suggested by the NRPB. 80 refs., 5 tabs

  17. The gastrointestinal absorption and urinary excretion of plutonium in male volunteers

    International Nuclear Information System (INIS)

    Ham, G.J.; Harrison, J.D.

    2000-01-01

    The gastrointestinal absorption and urinary excretion of 244 Pu have been measured in five healthy adult males in a two-stage study. Firstly, the volunteers ingested about 10 14 atoms of 244 Pu in citrate solution with a mid-day meal and urinary excretion was measured for the following 7-9 days. After a period of at least six months, the same volunteers were given an intravenous injection of 2x10 12 atoms of 244 Pu in citrate solution. Urinary excretion was then measured for the following 7-9 days and subsequently at intervals over periods up to 5-6 years. Fractional absorption of Pu from the gastrointestinal tract, calculated by comparing excretion for the two routes of administration, averaged 6x10 -4 , consistent with the ICRP value of 5x10 -4 . The results show a positive correlation between increasing age of the subjects, between 36 and 64 years of age, and increasing absorption of ingested Pu from 10 -4 to 10 -3 . In general, results for urinary excretion after injection are consistent with prediction of the current ICRP model although daily excretion after 5-6 years (3 subjects) averages 0.005% of the administered amount, about twice the predicted value. (author)

  18. Influence of chemical form, feeding regimen, and animal species on the gastrointestinal absorption of plutonium

    International Nuclear Information System (INIS)

    Bhattacharyya, M.H.; Larsen, R.P.; Cohen, N.; Ralston, L.G.; Oldham, R.D.; Moretti, E.S.; Ayres, L.

    1985-01-01

    We evaluated the effect of chemical form and feeding regimen on the gastrointestinal (GI) absorption of plutonium in adult mice at plutonium concentrations relevant to the establishment of drinking water standards. Mean fractional GI absorption values in fasted adult mice were: Pu(VI) bicarbonate, 15 x 10 -4 ; Pu(IV) bicarbonate, 20 x 10 -4 ; Pu(IV) nitrate (pH2), 17 x 10 -4 ; Pu(IV) citrate, 24 x 10 -4 ; and Pu(IV) polymer, 3 x 10 -4 . Values in fed adult mice were: Pu(VI) bicarbonate, 1.4 x 10 -4 ; Pu(IV) polymer, 0.3 x 10 -4 . Pu(VI) is the oxidation state in chlorinated drinking waters and Pu(IV) is the oxidation state in many untreated natural waters. To assess the validity of extrapolating data from mice to humans, we also determined the GI absorption of Pu(VI) bicarbonate in adult baboons with a dual-isotope method that does not require animal sacrifice. Fractional GI absorption values obtained by this method were 23 +- 10 x 10 -4 for fasted baboons (n=5) and 1.4 +- 0.9 x 10 -4 for fed baboons (n=3). We have so far validated this method in one baboon and are currently completing validation in two additional animals. At low plutonium concentrations, plutonium oxidation state [Pu(VI) vs Pu(IV)] and administration medium (bicarbonate vs nitrate vs citrate) had little effect on the GI absorption of plutonium in mice. Formation of Pu(IV) polymers and animal feeding decreased the GI absorption of plutonium 5- to 10-fold. The GI absorption of Pu(VI) bicarbonate in both fed and fasted adult baboons appeared to be the same as in fed and fasted adult mice, respectively. 17 refs., 2 tabs

  19. Uranium gastrointestinal absorption: the F1 factor in humans

    International Nuclear Information System (INIS)

    Zamora, M.L.; Zielinski, J.M.; Meyerhof, D.; Moodie, G.; Falcomer, R.; Tracy, B.

    2003-01-01

    The present investigation was undertaken by the Department of Health, Canada, to determine the most appropriate value to use for uranium gastrointestinal absorption (f 1 ) in setting the guideline for drinking water. Fifty participants, free from medical problems, were recruited from two communities: a rural area where drinking water, supplied from drilled wells, contained elevated levels of uranium and an urban area where the water supplied by the municipal water system contained -1 . Uranium intake through food, drinking water and other beverages was monitored using the duplicate diet approach. Intake and excretion were measured by inductively coupled plasma-mass spectrometry (ICP-MS) in samples collected concurrently from the same individuals over a 3 d period. The range of f 1 values was between 0.001 to 0.06, with a median of 0.009. These values were independent of gender, age, duration of exposure, daily total uranium intake and allocation of intake between food and water. Consistent with the recommendation of ICRP Publication 69, 78% were below 0.02. (author)

  20. Enhancing effect of bile salts on gastrointestinal absorption of insulin ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of co-administration of two absorption enhancing bile alts, sodium glycocholate (NaGc) and sodium salicylate (NaSal), on insulin absorption via intestinal targeted delivery system. Methods: Insulin (10 IU/kg), associated with and without absorption enhancers (5 % enhancer solution of ...

  1. Gastrointestinal absorption of plutonium in mice, rats, and dogs: application to establishing values of f1 for soluble plutonium

    International Nuclear Information System (INIS)

    Bhattacharyya, M.H.; Larsen, R.P.; Oldham, R.D.; Moretti, E.S.; Spaletto, M.I.

    1985-04-01

    The gastrointestinal (GI) absorption of plutonium was measured in mice, rats, and dogs under conditions relevant to setting drinking water standards. The fractional GI absorption of Pu(VI) in adult mice was 2 x 10 -4 (0.02%) in fed mice and 2 x 10 -3 (0.2%) in fasted mice. The GI absorption of plutonium was independent of plutonium oxidation state, administration medium, and plutonium concentration; absorption was dependent upon animal species, state of animal fasting, state of Pu(IV) hydrolysis, and age of the animal. Fractional GI absorption values ranged from 3 x 10 -5 (0.003%) for hydrolyzed Pu(IV) administered to fed adult mice to 7 x 10 -3 (0.7%) for Pu(VI) administered to fed neonatal rats. From analysis of our data, we suggested values of f 1 (the fraction transferred from gut to blood in humans) for use in establishment of oral limits of exposure to plutonium. For an acute exposure in the occupational setting, we proposed one value of f 1 for fed (2 x 10 -4 ) and one for fasted (2 x 10 -3 ) individuals. For the environmental setting, we developed two approaches to obtaining values of f 1 ; suggested values were 6 x 10 -4 and 4 x 10 -3 , respectively. Both approaches took into account effects of animal age and fasting. We discussed uncertainties in proposed values of f 1 and made recommendations for further research. 41 refs., 8 figs., 24 tabs

  2. Gastrointestinal absorption of large amounts of plutonium. Effect of valency state on transfer

    International Nuclear Information System (INIS)

    Lataillade, G.; Duserre, C.; Metivier, H.; Madic, C.; CEA Centre d'Etudes Nucleaires de Fontenay-aux-Roses, 92

    1989-01-01

    The gastrointestinal absorption of Pu, ingested in valency state III, IV, V or VI was studied in baboons. For each state, the absorption of Pu from masses ranging from 1 to 7 mg per kg of body weight was compared with that from masses ranging from 5 to 45 μg per kg of body weight. The mass ingested did not affect the gastrointestinal absorption of Pu(IV) or PU(VI), but for Pu(V) and to a lesser extent Pu(III), absorption clearly increased about 150-fold and 7-fold respectively, when large masses of Pu were ingested. When small masses were ingested, the valency state did not affect absorption. The increased Pu absorption observed after ingestion of large masses of Pu(V) or (III) might be due to the weak hydrolysis of these valency states. (author)

  3. Absorption and excretion of zinc, cadmium and mercury in the gastrointestinal tract

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, H [National Inst. of Radiological Sciences, Chiba (Japan)

    1975-10-01

    The absorption and excretion of inorganic zinc, cadmium and mercury in the gastrointestinal tract were compared using /sup 65/Zn, /sup 109/Cd and /sup 203/Hg. A single dose of /sup 65/Zn, /sup 109/Cd or /sup 203/Hg was administered orally or injected intravenously to investigate the distribution, excretion into bile and excretion into feces or urine. Absorption and excretion through the gastrointestinal tract of mice were studied by the tied loop method. Groups of eight mice or rats were used to measure the radioactivity in sample with a scintillation counter. Most of the orally administered /sup 65/Zn, /sup 109/Cd or /sup 203/Hg was excreted into feces and was less absorbed by the gastrointestinal tract, respectively. Absorption rate in the gastrointestinal tract was as follows: /sup 203/Hg>/sup 65/Zn>/sup 109/Cd. Intravenously injected /sup 65/Zn, /sup 109/Cd or /sup 203/Hg was escreted into the gastrointestinal tract through the gastrointestinal wall and bile duct, respectively. Excretion rate in the gastrointestinal tract was as follows: /sup 65/Zn>/sup 203/Hg>/sup 109/Cd. When comparing the absorption and excretion in each gastrointestinal tract divided into 10 parts, /sup 65/Zn, and /sup 109/Cd were relatively well absorbed from the upper and lower part of small intestine and excreted into the upper, middle, lower part. /sup 203/Hg was relatively well absorbed from the upper, lower part of small intestine and excreted into the stomach and the caecum. The major organs that accumulated absorbed /sup 65/Zn, /sup 109/Cd or /sup 203/Hg were the pancreas and liver, liver and kidney, kidney and liver, respectively.

  4. Enhancing Effect of Bile Salts on Gastrointestinal Absorption of Insulin

    African Journals Online (AJOL)

    glycocholate (NaGc) and sodium salicylate (NaSal), on insulin absorption via intestinal targeted delivery system. ... medication in diabetes mellitus treatment but ... emulsion, then the temperature was dropped to 4 ... using abdominal incision.

  5. A review of whole-body counting techniques appropriate to the study of gastrointestinal absorption

    International Nuclear Information System (INIS)

    Boddy, K.

    1976-01-01

    The wide range of whole-body counters in use for, or applicable to, the study of gastrointestinal absorption is reviewed. Shielded-room or high-sensitivity shadow-shield counters will generally be required only when there is a separate need to measure total body potassium or in studies involving pregnancy or children. For measuring gastrointestinal absorption per se, it is concluded that very simple whole-body counters of the shadow-shield or partial-shield type are usually satisfactory. These systems are of lower cost, and an economic justification for their use is derived by comparing their costs with those of hospitalizing patients for alternative investigations of gastrointestinal absorption. A resume of the general methodology is presented and some operational features and precautions are described. (author)

  6. Drug gastrointestinal absorption in rat: Strain and gender differences.

    Science.gov (United States)

    Oltra-Noguera, Davinia; Mangas-Sanjuan, Victor; González-Álvarez, Isabel; Colon-Useche, Sarin; González-Álvarez, Marta; Bermejo, Marival

    2015-10-12

    Predictive animal models of intestinal drug absorption are essential tools in drug development to identify compounds with promising biopharmaceutical properties. In situ perfusion absorption studies are routinely used in the preclinical setting to screen drug candidates. The objective of this work is to explore the differences in magnitude and variability on intestinal absorption associated with rat strain and gender. Metoprolol and Verapamil absorption rate coefficients were determined using the in situ closed loop perfusion model in four strains of rats and in both genders. Strains used were Sprague-Dawley, Wistar-Han, Wistar-Unilever, Long-Evans and CD∗IGS. In the case of Metoprolol only CD∗IGS and Wistar Unilever showed differences between males and females. For Verapamil, Wistar Han and Sprague-Dawley strains do not show differences between male and female rats. That means that in these strains permeability data from male and female could be combined. In male rats, which are commonly used for permeability estimation, there were differences for Metoprolol permeability between Sprague-Dawley (with lower permeability values) and the other strains, while for Verapamil Sprague-Dawley and Wistar-Han showed the lower permeability values. In conclusion, the selection of rat's strain and gender for intestinal absorption experiments is a relevant element during study design and data from different strains may not be always comparable. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Studies of Se-75 labelled bile acid analogue absorption in different forms of gastrointestinal diseases using a whole body counter

    International Nuclear Information System (INIS)

    Grebe, S.F.; Sattler, E.L.; Rinkenberger, C.; Bodenmueller, D.; Grebe, S.K.G.; Mueller, K.D.; Mueller, H.; Faengewisch, G.L.; Heckers, H.; Steckenmesser, R.

    1996-01-01

    It is possible to detect disturbances of bile acid absorption using a whole body counter after administration of Se-75 labelled bile acid analogues. We scrutinized the benefit of a modification of the test method. We investigated 77 patients with different forms of a gastrointestinal disease. After application of Se 75 homotaurocholic acid we measured patient-activity up to 7 days later including whole-body profile scans in the first 6 h. The fractional retention after 7 days was between 20 and 67%. In cases of impaired absorption it was below 12%. Patients with liver diseases and afer cholecystectomy (without bile acid resorption disturbance) showed normal values. Patients with Crohn's disease of the ileum or with intestinal ileas by-pass or with colestyramine treatment or with disturbance of vitamin B12-absorption or with cystic fibrosis showed a disturbance of bile acid absorption. The normal whole-body half-life was more than 2.8 days. The 24 and 72 h values were 62 and 31% in cases with normal absorption. Smaller values are signs of bile acid malabsorption. Impulse rates measured with the whole body counter are of an order of magnitude that allows to reduce the usually administered dose of 37 kBq to 9.25 kBq. This is an efficient method to detect disturbances of bile acid absorption. The usually adminstered activity of 37 kBq can be reduced to 9.25 kBq. (orig./MG) [de

  8. The impact of alcohol om 241Am gastrointestinal absorption, distribution and metabolism kinetics in rats

    International Nuclear Information System (INIS)

    Zalikin, G.A.; Moskalev, Yu.I.; Nisimov, P.G.

    1986-01-01

    It is shown that alcohol may intensify gastrointestinal absorption of transuranium nuclides. Some intensification of 241 Am metabolism kinetics in rats and accelerated radionuclide excretion from skeleton are noticed that is due to toxic ethanol effect. Investigations in the above direction are thought to be interesting for development under conditions of chronic effect of different alcohol doses and transuranium nuclide incorporation

  9. Plutonium and neptunium absorption from the gastrointestinal tract of neonatal baboons

    International Nuclear Information System (INIS)

    Lataillade, Ghislaine; Duserre, Claude; Rateau, Gerard; Verry, Monique; Fritsch, Paul; Metivier, Henri

    1992-06-01

    Nineteen baboons aged 1 to 310 days were given oral doses of 238 Pu citrate or 239 Np nitrate. Gastrointestinal (GI) absorption of Pu and Np were higher than those observed in adults. The values of Pu GI absorption were 0.22% at 1 d, 0.17% at 17 d then about 0.10% until 177 d of age. From 195 d onwards, GI absorption was about 0.02% vs adult values (0.008%). GI absorption of neptunium decreased rapidly with age from 1.71% at 4 d to 0.14% at 6 d and remained at this value until 26 d. From 77 d onwards Np GI absorption was decreased to adult value (0.042%). Gastrointestinal retention associated with GI absorption was small, below 0.4% for Pu and 0.2% for Np. Np and Pu was mainly retained in the small intestine. Pu was retained in the ileum wall till 66 d, and afterwards in the duodenum wall. Histological study of Pu retention showed that it was confined to the macrophages under the ileum villi epithelial cells. Np did not seem to have a well-defined retention compartment. Retention occurred first in the ileum wall up to 6 d, afterwards it was divided between the ileum and duodenum walls up to 77 d and finally, between the duodenum and jejunum walls from 132 days of age onwards. The study shows a difference between Np and Pu GI absorption in neonatal baboons. Np GI absorption decreased to adult value in less than 3 months whereas Pu GI absorption decreased to adult value within 195 days. Our Pu results demonstrated that, the tenfold increase of actinides gastrointestinal transfer proposed by ICRP up to 12 months of age in newborn humans seems acceptable. (authors) [fr

  10. Fractionated total body irradiation; the gastrointestinal toxicity versus the conditioning effect for bone marrow transplantation with different fractionation schedules

    International Nuclear Information System (INIS)

    Walma, E.P.; Klapwijk, W.M.; Miller, A.M.

    1982-01-01

    In most cases, bone marrow transplantation is preceded by a conditioning regimen employing irradiation and/or cytotoxic drugs. The authors are searching for better fractionation schedules in order to optimize the conditioning regimen prior to transplantation of stem-cell-enriched bone marrow. They have determined damage to the gastrointestinal tract in dogs and mice after total body irradiation in mice and dogs following a number of fractionation schedules, and these results are presented. The schedules were chosen such as to minimize the interval between irradiation and the bone marrow transplantation and to maximize clinical feasibility. (Auth./C.F.)

  11. Gastrointestinal absorption and retention of polonium in adult and newborn rats and guinea pigs

    International Nuclear Information System (INIS)

    Haines, J.W.; Naylor, G.P.L.; Pottinger, H.; Harrison, J.D.

    1993-01-01

    The gastrointestinal absorption of 210 Po was determined by comparing tissue retention after oral and systemic administration. The results indicate an increase in absorption in adult rats for 210 Po administered in liver compared with 210 Po nitrate with estimated absorption of 5 and 13%, respectively. For 210 Po citrate, values of about 7% were obtained in 1-day-old neonate and adult rats while absorption in guinea pigs was estimated to be about 23% in 1-day-old neonates, 17% in 5-day-old neonates, and 9% in adults. Gut retention of ingested 210 Po in neonates was high in rats but not guinea pigs. In adult animals, but not neonates, the liver accounted for a greater proportion of 210 Po reaching the bloodstream after ingestion than after systemic injection. The significance of these results is discussed in relation to current assumptions made in the calculation of doses from 210 Po. (author)

  12. Gastrointestinal absorption of neptunium in primates: effect of ingested mass, diet, and fasting

    International Nuclear Information System (INIS)

    Metivier, H.; Bourges, J.; Fritsch, P.; Nolibe, D.; Masse, R.

    1986-01-01

    Absorption and retention of neptunium were determined in baboons after intragastric administration of neptunium nitrate solutions at pH 1. The effects of mass, diet, and fasting on absorption were studied. At higher mass levels (400-800 micrograms Np/kg), absorption was about 1%; at lower mass intakes (0.0009-0.005 micrograms Np/kg), absorption was reduced by 10- to 20-fold. The addition of an oxidizing agent (Fe3+) increased gastrointestinal absorption and supported the hypothesis of a reduction of Np (V) when loss masses were ingested. Diets depleted of or enriched with hydroxy acids did not modify retention of neptunium but increased urinary excretion with increasing hydroxy acid content. The diet enriched with milk components reduced absorption by a factor of 5. Potatoes increased absorption and retention by a factor 5, not necessarily due to the effect of phytate. Fasting for 12 or 24 h increased retention and absorption by factors of about 3 and 10, respectively. Data obtained in baboons when low masses of neptunium were administered suggest that the f1 factor used by ICRP should be decreased. However, fasting as encountered in certain nutritional habits is a factor to be taken into consideration

  13. Gastrointestinal absorption of actinides: a review with special reference to primate data

    International Nuclear Information System (INIS)

    Burkart, W.

    1984-01-01

    Large scale geological burial of transuranic wastes from fission power production may expose segments of future generations to trace amounts of actinides in water and food, which, via gastrointestinal absorption, could result in internal doses of alpha radiation. Gastrointestinal absorption of actinide elements is a poorly understood process. Experimental studies, primarily using rodents, often produce ambiguous results with order of magnitude fluctuations in estimates of GI absorption. Since experimental conditions like the chemical form of the fed actinides or reducing and complexing capacity of the stomach content, influence the GI transfer factor in seemingly unpredictable ways, only a better understanding of events at the molecular level will enable more reliable predictions to be made of the organ burdens resulting from actinides passing through the digestive tract. From a review of the existing literature it is apparent that in vitro research data in the area of GI uptake mechanisms (i.e. transport mediated by ion carriers in body fluids and across cell membranes) are virtually non-existant. In view of the uncertainties linked to in vivo uptake experiment, models which approximate man, i.e. derived from non-human primate studies, should be the best choice of experimental systems in which to determine reliable estimates for gastrointestinal transfer factors of actinide elements. (Auth.)

  14. The gastrointestinal absorption of organically bound forms of plutonium in fed and fasted hamsters

    International Nuclear Information System (INIS)

    Harrison, J.D.; Cooper, J.R.; Bomford, J.A.; David, A.J.

    1986-01-01

    Values of about 0.005-0.01% were obtained for the absorption in fed hamsters of plutonium ingested as Pu 4+ citrate, isocitrate, phytate and malate complexes and Pu 3+ ascorbate compared with about 0.003-0.004% for Pu 4+ nitrate. Replacing drinking water with tea did not affect the result for Pu 4+ nitrate. Fasting hamsters for 8 h before the administration of plutonium citrate increased absorption to 0.1-0.2%. An extra period of fasting for 4 h after administration did not lead to a further increase in absorption. Similar values were also obtained when plutonium citrate was administered after a 24 h fast, followed either by immediate access to food or a further 4 h fast. In hamsters fasted for 24 h before administration of either Pu 3+ ascorbate or Pu 4+ nitrate, about 6-7 per cent of the ingested plutonium was retained in the gastrointestinal tract after one week. At three weeks after ingestion of Pu 3+ ascorbate, gastrointestinal retention had fallen 100-fold without an increase in absorption. (author)

  15. Continued studies of the gastrointestinal absorption of plutonium by rodents: relationships to feeding regimen and age of animals

    International Nuclear Information System (INIS)

    Larsen, R.P.; Bhattacharyya, M.H.; Oldham, R.D.; Moretti, E.S.; Spaletto, M.I.

    1982-01-01

    In mice that are consuming food ad libitum the gastrointestinal absorption of plutonium (and its subsequent retention in liver and skeleton) has been shown to be a factor of about 10 lower than it is in the fasted anaimal. It has been found that the time required to achieve the fasted state is less than two hours for mice that are at the end of their diurnal, inactive phase and between 4 and 8 hours for mice that are 4 hours into their active phase. The absorption of plutonium appears to depend on the nature of materials in the G.I. tract, i.e., properties of the food consumed, rather than amounts present. The fractional absorption of plutonium from the G.I. tract by the rat decreases with age in the unweaned animal, from 7 x 10 - 3 on day 1 to 3 x 10 - 3 on day 19 (the latter value being the same as that for the fasted adult) and with weaning to 1 x 10 - 4 on day 29

  16. Profiling biopharmaceutical deciding properties of absorption of lansoprazole enteric-coated tablets using gastrointestinal simulation technology.

    Science.gov (United States)

    Wu, Chunnuan; Sun, Le; Sun, Jin; Yang, Yajun; Ren, Congcong; Ai, Xiaoyu; Lian, He; He, Zhonggui

    2013-09-10

    The aim of the present study was to correlate in vitro properties of drug formulation to its in vivo performance, and to elucidate the deciding properties of oral absorption. Gastrointestinal simulation technology (GST) was used to simulate the in vivo plasma concentration-time curve and was implemented by GastroPlus™ software. Lansoprazole, a typical BCS class II drug, was chosen as a model drug. Firstly, physicochemical and pharmacokinetic parameters of lansoprazole were determined or collected from literature to construct the model. Validation of the developed model was performed by comparison of the predicted and the experimental plasma concentration data. We found that the predicted curve was in a good agreement with the experimental data. Then, parameter sensitivity analysis (PSA) was performed to find the key parameters of oral absorption. The absorption was particularly sensitive to dose, solubility and particle size for lansoprazole enteric-coated tablets. With a single dose of 30 mg and the solubility of 0.04 mg/ml, the absorption was complete. A good absorption could be achieved with lansoprazole particle radius down to about 25 μm. In summary, GST is a useful tool for profiling biopharmaceutical deciding properties of absorption of lansoprazole enteric-coated tablets and guiding the formulation optimization. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  17. Chemical form of technetium in corn (Zea mays) and the gastrointestinal absorption of plant-incorporated Tc by laboratory rats

    Energy Technology Data Exchange (ETDEWEB)

    Garten, C.T. Jr.; Myttenaere, C.; Vandecasteele, C.M.; Kirchmann, R.; Van Bruwaene, R.

    1984-01-01

    The food chain availability of technetium incorporated into plant tissue, its chemical form in corn leaves, and the potential for gastrointestinal absorption of plant-incorporated technetium was investigated. Technetium-95m was incorporated into corn leaves via root uptake. Chemical fractionation of the /sup 95m/Tc in leaves showed that 60% was extractable with boiling ethanol and weak mineral acids. The remainder was associated with cell walls and was extractable by harsh chemical treatment. Gel permeation chromatography of the cytosol, indicated that 50% of the /sup 95m/Tc co-chromatographed with anionic pertechnetate; however, it was impossible to distinguish if this pure pertechnetate or technetium complexed with organic molecules. Technetium-95m was administered to laboratory rats in a single dose as: (1) intravenous injection of pertechnetate, (2) pertechnetate mixed with standard laboratory food, and (3) a meal containing /sup 95m/Tc biologically incorporated into corn leaves. High concentrations of /sup 95m/Tc were found in the thyroids, hair, kidneys, and liver of rats. Technetium rapidly disappeared from the liver, kidneys, and other tissues, but remained in the thyroids and hair. Urinary excretion of technetium decreased, and fecal excretion increased when technetium was fed to rats as a /sup 95m/Tc incorporated into corn leaves. The percent of the administered dose absorbed into thyroid gland and the kidneys was less when technetium was biologically incorporated into corn leaves than when pertechnetate was mixed with food. Biological incorporation of technetium into plants appears to reduce its potential for food chain transfer by decreasing its availability for gastrointestinal absorption. 5 references, 4 figures, 3 tables.

  18. Chemical form of technetium in corn (Zea mays) and the gastrointestinal absorption of plant-incorporated Tc by laboratory rats

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.; Myttenaere, C.; Vandecasteele, C.M.; Kirchmann, R.; Van Bruwaene, R.

    1984-01-01

    The food chain availability of technetium incorporated into plant tissue, its chemical form in corn leaves, and the potential for gastrointestinal absorption of plant-incorporated technetium was investigated. Technetium-95m was incorporated into corn leaves via root uptake. Chemical fractionation of the /sup 95m/Tc in leaves showed that 60% was extractable with boiling ethanol and weak mineral acids. The remainder was associated with cell walls and was extractable by harsh chemical treatment. Gel permeation chromatography of the cytosol, indicated that 50% of the /sup 95m/Tc co-chromatographed with anionic pertechnetate; however, it was impossible to distinguish if this pure pertechnetate or technetium complexed with organic molecules. Technetium-95m was administered to laboratory rats in a single dose as: (1) intravenous injection of pertechnetate, (2) pertechnetate mixed with standard laboratory food, and (3) a meal containing /sup 95m/Tc biologically incorporated into corn leaves. High concentrations of /sup 95m/Tc were found in the thyroids, hair, kidneys, and liver of rats. Technetium rapidly disappeared from the liver, kidneys, and other tissues, but remained in the thyroids and hair. Urinary excretion of technetium decreased, and fecal excretion increased when technetium was fed to rats as a /sup 95m/Tc incorporated into corn leaves. The percent of the administered dose absorbed into thyroid gland and the kidneys was less when technetium was biologically incorporated into corn leaves than when pertechnetate was mixed with food. Biological incorporation of technetium into plants appears to reduce its potential for food chain transfer by decreasing its availability for gastrointestinal absorption. 5 references, 4 figures, 3 tables

  19. Reanalysis of gastrointestinal absorption factors for plutonium and other actinide elements

    International Nuclear Information System (INIS)

    Bhattacharyya, M.H.; Larsen, R.P.; Toohey, R.E.; Moretti, E.S.; Oldham, R.D.; Spaletto, M.I.; Engel, M.C.

    1981-01-01

    This project studies the gastrointestinal absorption of plutonium and other actinide elements relevant to nuclear power production, at concentrations at or below their respective maximum permissible concentrations (MPC's) in drinking water, using high specific activity isotopes. The gastrointestinal absorption of plutonium is measured in mice, rats, and dogs exposed to plutonium either via drinking water or by gavage. Plutonium concentrations are determined in liver and eviscerated carcass at 6 days (mice and rats) or 4 weeks (dogs). Administered solutions are 1 x 10 -10 M in Pu (the molar concentration at MPC for 239 Pu) and contain one of several high specific activity isotopes ( 237 Pu, 47-day half-life; 236 Pu, 2.8-year half-life; 238 Pu, 86-year half-life). Fasted mice and rats, administered plutonium solutions that are: (1) low in concentration (10- 10 M); and (2) carefully prepared to assure a given oxidation state and to avoid hydrolysis and polymes, and major policy issues. The first HEED for near-term battery energy storage systems (lead/acid, nickel/zinc, and nickel/iron) astention being paid to potential releases of radionuclides at relatively short times after disposal

  20. Human in vivo and in vitro studies on gastrointestinal absorption of titanium dioxide nanoparticles.

    Science.gov (United States)

    Jones, Kate; Morton, Jackie; Smith, Ian; Jurkschat, Kerstin; Harding, Anne-Helen; Evans, Gareth

    2015-03-04

    The study was designed to conduct human in vivo and in vitro studies on the gastrointestinal absorption of nanoparticles, using titanium dioxide as a model compound, and to compare nanoparticle behaviour with that of larger particles. A supplier's characterisation data may not fully describe a particle formulation. Most particles tested agreed with their supplied characterisation when assessed by particle number but significant proportions of 'nanoparticle formulations' were particles >100nm when assessed by particle weight. Oral doses are measured by weight and it is therefore important that the weight characterisation is taken into consideration. The human volunteer studies demonstrated that very little titanium dioxide is absorbed gastrointestinally after an oral challenge. There was no demonstrable difference in absorption for any of the three particle sizes tested. All tested formulations were shown to agglomerate in simulated gastric fluid, particularly in the smaller particle formulations. Further agglomeration was observed when dispersing formulations in polymeric or elemental foods. Virtually no translocation of titanium dioxide particles across the cell layer was demonstrated. This study found no evidence that nanoparticulate titanium dioxide is more likely to be absorbed in the gut than micron-sized particles. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

  1. Gastrointestinal absorption and retention of plutonium and uranium in the baboon

    International Nuclear Information System (INIS)

    Larsen, R.P.; Bhattacharyya, M.H.; Oldham, R.D.; Moretti, E.S.; Cohen, N.

    1984-01-01

    Individual isotopes of plutonium and uranium were administered both intragastrically and intravenously to a baboon. Samples of urine, faces, blood, and tissues were taken and are now being analyzed. Preliminary results indicate that the fractional absorptions of plutonium and uranium were 1 x 10 -3 and 1 x 10 -2 , respectively, and their retentions about one month later were about 20% and 10%, respectively, of the amounts absorbed. The fractional retentions of the intravenously injected plutonium and uranium at that time were 0.90 and 0.07. 13 references, 1 figure, 3 tables

  2. An In Silico Knockout Model for Gastrointestinal Absorption Using a Systems Pharmacology Approach - Development and Application for Ketones.

    Directory of Open Access Journals (Sweden)

    Vittal Shivva

    Full Text Available Gastrointestinal absorption and disposition of ketones is complex. Recent work describing the pharmacokinetics (PK of d-β-hydroxybutyrate (BHB following oral ingestion of a ketone monoester ((R-3-hydroxybutyl (R-3-hydroxybutyrate found multiple input sites, nonlinear disposition and feedback on endogenous production. In the current work, a human systems pharmacology model for gastrointestinal absorption and subsequent disposition of small molecules (monocarboxylic acids with molecular weight < 200 Da was developed with an application to a ketone monoester. The systems model was developed by collating the information from the literature and knowledge gained from empirical population modelling of the clinical data. In silico knockout variants of this systems model were used to explore the mechanism of gastrointestinal absorption of ketones. The knockouts included active absorption across different regions in the gut and also a passive diffusion knockout, giving 10 gut knockouts in total. Exploration of knockout variants has suggested that there are at least three distinct regions in the gut that contribute to absorption of ketones. Passive diffusion predominates in the proximal gut and active processes contribute to the absorption of ketones in the distal gut. Low doses are predominantly absorbed from the proximal gut by passive diffusion whereas high doses are absorbed across all sites in the gut. This work has provided mechanistic insight into the absorption process of ketones, in the form of unique in silico knockouts that have potential for application with other therapeutics. Future studies on absorption process of ketones are suggested to substantiate findings in this study.

  3. Radiation injuries of the gastrointestinal tract in Hodgkin's disease: the role of exploratory laparotomy and fractionation

    International Nuclear Information System (INIS)

    Gallez-Marchal, D.; Fayolle, M.; Henry-Amar, M.; Le Bourgeois, J.P.; Rougier, P.; Cosset, J.M.

    1984-01-01

    Out of 134 patients irradiated below the diaphragm to a dose of 40 Gy for Hodgkin's disease at the Institut Gustave-Roussy, 19 (14%) were subsequently found to present with radiation injuries of the gastrointestinal tract. Since five patients presented with two different injuries, 24 radiolesions were observed. Most of them (17 out of 24) were gastric or duodenal. Twelve (out of 24) were ulcers. Nine patients required surgery. A complete cure of the radiation injuries was obtained in 15 out of 19 patients. Sex, age, stage, histology or initial chemotherapy were not found to play a role in the occurrence of radiation damage. On the contrary, the role of a previous exploratory laparotomy appeared important; for the patients who underwent laparotomy and irradiation, the complication rate was 23%. For the patients treated by irradiation alone, the complication rate was 7% (p < 0.01). Fractionation was found to be another important parameter: for 52 patients treated using 3 weekly fractions of 3.3 Gy, the complication rate was 25% compared to 8% (p < 0.01) for 76 patients treated using 4 weekly fractions of 2.5 Gy. Combining these two factors, the authors found a 42% complication rate for the group of patients who underwent laparotomy and who were treated by means of 3 fractions of 3.3 Gy per week, whereas patients irradiated using 4 weekly fractions of 2.5 Gy, without any previous laparotomy, has only a 5% complication risk (p < 0.001). (Auth.)

  4. Influence of pH on Drug Absorption from the Gastrointestinal Tract: A Simple Chemical Model

    Science.gov (United States)

    Hickman, Raymond J. S.; Neill, Jane

    1997-07-01

    A simple model of the gastrointestinal tract is obtained by placing ethyl acetate in contact with water at pH 2 and pH 8 in separate test tubes. The ethyl acetate corresponds to the lipid material lining the tract while the water corresponds to the aqueous contents of the stomach (pH 2) and intestine (pH 8). The compounds aspirin, paracetamol and 3-aminophenol are used as exemplars of acidic, neutral and basic drugs respectively to illustrate the influence which pH has on the distribution of each class of drug between the aqueous and organic phases of the model. The relative concentration of drug in the ethyl acetate is judged by applying microlitre-sized samples of ethyl acetate to a layer of fluorescent silica which, after evaporation of the ethyl acetate, is viewed under an ultraviolet lamp. Each of the three drugs, if present in the ethyl acetate, becomes visible as a dark spot on the silica layer. The observations made in the model system correspond well to the patterns of drug absorption from the gastrointestinal tract described in pharmacology texts and these observations are convincingly explained in terms of simple acid-base chemistry.

  5. Acute effects of carprofen and meloxicam on canine gastrointestinal permeability and mucosal absorptive capacity.

    Science.gov (United States)

    Craven, Melanie; Chandler, Marge L; Steiner, Jörg M; Farhadi, Ashkan; Welsh, Elizabeth; Pratschke, Kathryn; Shaw, Darren J; Williams, David A

    2007-01-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently prescribed to dogs for their analgesic, antipyretic, and anti-inflammatory properties. Their beneficial actions can be offset by gastrointestinal (GI) toxicosis. Endoscopy has traditionally been employed to detect GI lesions, but alterations in GI permeability precede the development of mucosal damage. Carprofen and meloxicam alter GI permeability and mucosal absorptive capacity of dogs. Twenty adult dogs treated with an NSAID for >7 days were evaluated by permeability tests while receiving either carprofen (10 dogs) or meloxicam (10 dogs). Prospective, longitudinal observational study. A 6-sugar permeability test (sucrose, lactulose, rhamnose, 3-O-methyl-D-glucose, D-xylose, and sucralose) was performed on the day before NSAID treatment, and after 3 and 8 days of treatment. There were no significant differences in the urinary recovery ratios of lactulose: rhamnose, D-xylose: 3-O-methyl-D-glucose, or sucralose recovery within either group at any time during the study. Sucrose permeability in the meloxicam group did not alter significantly over time. However, sucrose permeability in the carprofen group decreased significantly by day 3 (P = .049) and increased again by day 8 (P = .049), to a level that was not significantly different to permeability before treatment (P = .695). The absence of increased GI permeability and diminished mucosal absorptive capacity in this group of dogs does not support the development of acute GI toxicosis during treatment with either meloxicam or carprofen.

  6. The gastrointestinal absorption and retention of niobium in adult and newborn guinea pigs

    International Nuclear Information System (INIS)

    Harrison, J.D.; Haines, J.W.; Popplewell, D.S.

    1990-01-01

    The gastrointestinal absorption of 95 Nb ingested in milk by adult guinea pigs on a milk-supplemented diet was estimated as 0.8±0.2% (SEM; n=4) and a value of 1.4±0.2% obtained for guinea pigs fasted for 24 h before and 2 h after oral administration of 95 Nb in a citrate solution. The absorption in 2-day-old animals given the 95 Nb-citrate solution was estimated as 1.5±0.2% (SEM; n=3). These results support the values currently used for radiological protection purposes to calculate doses from the ingestion of niobium isotopes; these are 1% for adults and 2% for infants in the first year of life. Intestinal retention of niobium in newborn guinea pigs was low, unlike retention in other species, but consistent with observations of the retention of other elements in guinea pigs. It is considered that retention in human neonates is likely to be most similar to that in guinea pigs. (author)

  7. The coupled effect of fiber volume fraction and void fraction on hydraulic fluid absorption of quartz/BMI laminates

    Science.gov (United States)

    Hurdelbrink, Keith R.; Anderson, Jacob P.; Siddique, Zahed; Altan, M. Cengiz

    2016-03-01

    Bismaleimide (BMI) resin with quartz (AQ581) fiber reinforcement is a composite material frequently used in aerospace applications, such as engine cowlings and radomes. Various composite components used in aircrafts are exposed to different types of hydraulic fluids, which may lead to anomalous absorption behavior over the service life of the composite. Accurate predictive models for absorption of liquid penetrants are particularly important as the composite components are often exposed to long-term degradation due to absorbed moisture, hydraulic fluids, or similar liquid penetrants. Microstructural features such as fiber volume fraction and void fraction can have a significant effect on the absorption behavior of fiber-reinforced composites. In this paper, hydraulic fluid absorption characteristics of quartz/BMI laminates fabricated from prepregs preconditioned at different relative humidity and subsequently cured at different pressures are presented. The composite samples are immersed into hydraulic fluid at room temperature, and were not subjected to any prior degradation. To generate process-induced microvoids, prepregs were conditioned in an environmental chamber at 2% or 99% relative humidity at room temperature for a period of 24 hours prior to laminate fabrication. To alter the fiber volume fraction, the laminates were fabricated at cure pressures of 68.9 kPa (10 psi) or 482.6 kPa (70 psi) via a hot-press. The laminates are shown to have different levels of microvoids and fiber volume fractions, which were observed to affect the absorption dynamics considerably and exhibited clear non-Fickian behavior. A one-dimensional hindered diffusion model (HDM) was shown to be successful in predicting the hydraulic fluid absorption. Model prediction indicates that as the fabrication pressure increased from 68.9 kPa to 482.6 kPa, the maximum fluid content (M∞) decreased from 8.0% wt. to 1.0% wt. The degree of non-Fickian behavior, measured by hindrance coefficient (

  8. The metabolism and gastrointestinal absorption of neptunium and protactinium in adult baboons

    International Nuclear Information System (INIS)

    Ralston, L.G.; Cohen, N.; Bhattacharyya, H.; Larsen, R.P.; Ayres, L.; Oldham, R.D.; Moretti, E.S.

    1985-01-01

    The metabolism of neptunium and protactinium was studied in adult female baboons following intravenous injection and intragastric intubation. Neptunium-239, Np-237, and Pa-233 were prepared as either citrate-buffer, nitrate, or bicarbonate solutions with oxidation states of (V) and (VI). Samples of blood, urine, feces and autopsy tissues were measured by gamma spectrometry. Retention of neptunium and protactinium was determined in vivo using whole and partial body gamma-scintillation spectrometry with [NaI-CsI(T1)] detectors. Fed and fasted baboons were administered solutions of Np(VI) bicarbonate (10/sup -8/ to 10/sup -1/ mg/kg) and Pa(V) citrate-buffer (10/sup -9/ mg/kg) by gavage. The gastrointestinal absorption value for neptunium in two fasted baboons, sacrificed at 1 day post administration, was determined to be 0.92 +- 0.04%. Of the total amount of neptunium absorbed, 52 +- 3% was retained in bone, 6 + 2% was in liver, and 42 +- 0.1% was excreted in urine. The metabolism of neptunium followed oral and iv administrations was found to be similar. This observation was also true for baboons which had received oral and iv doses of protactinium. A method was developed to estimate GI absorption values for both nuclides in baboons, which were not sacrificed, by comparison of activities present in bioassay samples after injection and gavage. Absorption values calculated by this method for neptunium and protactinium in fasted baboons were 1.8 +- 0.8% and 0.65 +- 0.01%, respectively. Values for fed animals were 1 to 2 orders of magnitude less than those for fasted animals. Further experiments are currently underway to evaluate this assay technique

  9. Metabolism and gastrointestinal absorption of neptunium and protactinium in adult baboons

    International Nuclear Information System (INIS)

    Ralston, L.G.; Cohen, N.; Bhattacharyya, M.H.; Larsen, R.P.; Ayres, L.; Oldham, R.D.; Moretti, E.S.

    1985-01-01

    The metabolism of neptunium and protactinium was studied in adult female baboons following intravenous injection and intragastric intubation. Immediately following intravenous injection (10 -1 to 10 -10 mg Np per kg body wt), neptunium cleared rapidly from blood, deposited primarily in the skeleton (54 +- 5%) and liver (3 +- 0.2%), and was excreted predominantly via urine (40 +- 3%). For the first year post injection, neptunium was retained with a biological half-time of approx.100 days in liver and 1.5 +- 0.2 yr in bone. In comparison, injected protactinium (10 -9 mg/kg) was retained in blood in higher concentrations and was initially eliminated in urine to a lesser extent (6 +- 3%). In vivo measurements indicated that protactinium was retained in bone (65 +- 0.3%) with a half-time of 3.5 +- 0.6 yr. Differences in the physicochemical states of the neptunium or protactinium solutions injected did not alter the metabolic behavior of these nuclides. The gastrointestinal absorption value for neptunium in two fasted baboons, sacrificed at 1 day post administration, was determined to be 0.92 +- 0.04%. Of the total amount of neptunium absorbed, 52 +- 3% was retained in bone, 6 +- 2% was in liver, and 42 +- 0.1% was excreted in urine. A method was developed to estimate GI absorption values for both nuclides in baboons which were not sacrificed. Absorption values calculated by this method for neptunium and protactinium in fasted baboons were 1.8 +- 0.8% and 0.65 +- 0.01%, respectively. Values for fed animals were 1 to 2 orders of magnitude less than those for fasted animals. 14 refs., 3 figs., 4 tabs. (DT)

  10. Metabolism and gastrointestinal absorption of neptunium and protactinium in adult baboons

    Energy Technology Data Exchange (ETDEWEB)

    Ralston, L.G.; Cohen, N.; Bhattacharyya, M.H.; Larsen, R.P.; Ayres, L.; Oldham, R.D.; Moretti, E.S.

    1985-01-01

    The metabolism of neptunium and protactinium was studied in adult female baboons following intravenous injection and intragastric intubation. Immediately following intravenous injection (10/sup -1/ to 10/sup -10/ mg Np per kg body wt), neptunium cleared rapidly from blood, deposited primarily in the skeleton (54 +- 5%) and liver (3 +- 0.2%), and was excreted predominantly via urine (40 +- 3%). For the first year post injection, neptunium was retained with a biological half-time of approx.100 days in liver and 1.5 +- 0.2 yr in bone. In comparison, injected protactinium (10/sup -9/ mg/kg) was retained in blood in higher concentrations and was initially eliminated in urine to a lesser extent (6 +- 3%). In vivo measurements indicated that protactinium was retained in bone (65 +- 0.3%) with a half-time of 3.5 +- 0.6 yr. Differences in the physicochemical states of the neptunium or protactinium solutions injected did not alter the metabolic behavior of these nuclides. The gastrointestinal absorption value for neptunium in two fasted baboons, sacrificed at 1 day post administration, was determined to be 0.92 +- 0.04%. Of the total amount of neptunium absorbed, 52 +- 3% was retained in bone, 6 +- 2% was in liver, and 42 +- 0.1% was excreted in urine. A method was developed to estimate GI absorption values for both nuclides in baboons which were not sacrificed. Absorption values calculated by this method for neptunium and protactinium in fasted baboons were 1.8 +- 0.8% and 0.65 +- 0.01%, respectively. Values for fed animals were 1 to 2 orders of magnitude less than those for fasted animals. 14 refs., 3 figs., 4 tabs. (DT)

  11. Nanostructuring Biomaterials with Specific Activities towards Digestive Enzymes for Controlled Gastrointestinal Absorption of Lipophilic Bioactive Molecules.

    Science.gov (United States)

    Joyce, Paul; Whitby, Catherine P; Prestidge, Clive A

    2016-11-01

    This review describes the development of novel lipid-based biomaterials that modulate fat digestion for the enhanced uptake of encapsulated lipophilic bioactive compounds (e.g. drugs and vitamins). Specific focus is directed towards analysing how key material characteristics affect the biological function of digestive lipases and manipulate lipolytic digestion. The mechanism of lipase action is a complex, interfacial process, whereby hydrolysis can be controlled by the ability for lipase to access and adsorb to the lipid-in-water interface. However, significant conjecture exists within the literature regarding parameters that influence the activities of digestive lipases. Important findings from recent investigations that strategically examined the interplay between the interfacial composition of the lipid microenvironment and lipolysis kinetics in simulated biophysical environments are presented. The correlation between lipolysis and the rate of solubilisation and absorption of lipophilic compounds in the gastrointestinal tract (GIT) is detailed. Greater insights into the mechanism of lipase action have provided a new approach for designing colloidal carriers that orally deliver poorly soluble compounds, directly impacting the pharmaceutical and food industries. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Comparison of the gastrointestinal absorption and bioavailability of fenofibrate and fenofibric acid in humans.

    Science.gov (United States)

    Zhu, Tong; Ansquer, Jean-Claude; Kelly, Maureen T; Sleep, Darryl J; Pradhan, Rajendra S

    2010-08-01

    This study compared the gastrointestinal (GI) absorption characteristics and absolute bioavailability of fenofibric acid and fenofibrate (which is converted to fenofibric acid in vivo) in healthy volunteers. Treatments were delivered to the proximal small bowel, distal small bowel, and colon using a site-specific delivery system (Enterion capsule) and to the stomach by oral administration of equimolar doses. Serial blood samples were collected for 120 hours postdose and assayed for plasma fenofibric acid concentrations. The absolute bioavailability of each treatment was determined relative to 50 mg of fenofibric acid administered intravenously. Plasma exposure to fenofibric acid following fenofibric acid administration was approximately 1.5 times higher than that following fenofibrate administration for delivery to the proximal and distal small bowel and following oral administration, and it was approximately 5 times higher following colon delivery. The absolute bioavailability in the stomach, proximal small bowel, distal small bowel, and colon was approximately 81%, 88%, 84%, and 78%, respectively, for fenofibric acid and 69%, 73%, 66%, and 22%, respectively, for fenofibrate (P < .0001 and P = .033 for fenofibric acid vs fenofibrate in the colon and distal small bowel, respectively). In conclusion, fenofibric acid is well absorbed throughout the GI tract and has greater bioavailability than fenofibrate in all GI regions.

  13. Radioimmunoassay of 1-Deamino-8-D-Arginine Vasopressin and related peptides with special condsideration to their gastrointestinal absorption

    International Nuclear Information System (INIS)

    Lundin, S.

    1986-01-01

    A sensitive and specific radioimminoassy for 1-deamino-8-D-arginine vasopressin (DDAVP) was developed. Measurements of the analogue in extracted and non-extracted plasma yielded indentical results, the sensitivity was reduced with non-extracted samples. The assay was validated by correlating DDAVP blood levels to a biologic response (antidiuretic). Dilutions of plasma extracts containing DDAVP were parallel with the standard curve. Fractionations of extracted plasma DDAVP samples on HPLC revealed that immunoreactivity eluted as standard DDAVP. Prolonged infusion of DDAVP in rats did not alter pituitary secretion of oxytocin and vasopressin and urine osmolatity and volume changes were modest. DDAVP was absorbed from the gastrointestinal tract of humans, rats, rabbits and dogs in quantities sufficient to induce a biological response. Peak plasma concentrations were reached between 30-90 min after peptide administration. By the use of an in vitro model, the everted rat intestine, the transmucosal passage of a number of vasopressin analogues were tested. There was no clear-cut correlation between hydrophobicity and intestinal transport rates. Metabolic inhibitors and N/sub2/ did not decrease DDAVP transport. No transport maximum could be demonstrated over a 10/sup4/ fold concentration range. The distribution volume of /sup3/H-polyethyleneglycol was greater. then that of DDAVP in mucosal flakes. There was a close correlation between immunoassayable DDAVP levels and those found after HPLC analyses. It is proposed that DDAVP absorption occurs mainly by passive diffusion. The bioavailability of perorally ingested DDAVP in humans was about 1 percent. Minor amounts were excreted in urine

  14. Fractional intestinal absorption and retention of calcium measured by whole-body counting. Application of a power function model

    International Nuclear Information System (INIS)

    Pors Nielsen, S.; Baerenholdt, O.; Munck, O.

    1975-01-01

    By application of a power function model, fractional intestinal calcium absorption was investigated with a new technique involving whole-body counting after successive oral and intravenous administration of standard doses of 47 Ca. The fractional calcium retention 7 days after the oral load of 47 Ca was also measured. Fractional calcium retention averaged 30.3% in normal subjects and 11.5% in 11 patients with intestinal malabsorption. In the same groups fractional calcium absorption averaged 46.6% and 16.4%, respectively. Fractional calcium retention and intestinal calcium absorption were significantly correlated to body surface area, and there was a well-defined relation between fractional retention and absorption of calcium. These studies demonstrate that measurements of fractional retention and fractional intestinal absorption of calcium can be combined by the use of a whole-body counter, that fractional retention and intestinal absorption are proportional to total body surface area and therefore probably also to the total bone mass, and that fractional retention and absorption are so closely interrelated that frational absorption can be estimated from fractional retention with reasonable accuracy in normal subjects. (auth.)

  15. Gastrointestinal absorption of plutonium and uranium in fed and fasted adult baboons and mice: application to humans

    International Nuclear Information System (INIS)

    Bhattacharyya, M.H.; Larsen, R.P.; Oldham, R.D.; Cohen, N.; Ralston, L.G.; Moretti, E.S.; Ayres, L.

    1989-01-01

    Gastrointestinal (GI) absorption values of plutonium and uranium were determined in fed and fasted adult baboons and mice. For both baboons and mice, the GI absorptions of plutonium and uranium were 10 to 20 times higher in 24 h fasted animals than in fed ones. For plutonium, GI absorption values in baboons were almost identical to those in mice for both fed and fasted conditions, and values for fed animals agreed with estimates for humans. For uranium, GI absorption values in fed and fasted baboons were 6 to 7 times higher than those in mice, and agreed well with those fed and fasted humans. For one baboon that was not given its morning meal, plutonium absorption 2 h after the start of the active phase was the same as that in the 24 h fasted animals. In contrast, for baboons that received a morning meal, plutonium absorption did not rise to the value of 24 h fasted baboons even 8 h after the meal. We conclude that GI absorption values for plutonium and uranium in adult baboons are good estimates of the values in humans and that the values for the fasted condition should be used to set standards for oral exposure of persons in the workplace. (author)

  16. THE INTRINSIC FRACTIONS AND RADIO PROPERTIES OF LOW-IONIZATION BROAD ABSORPTION LINE QUASARS

    International Nuclear Information System (INIS)

    Dai Xinyu; Shankar, Francesco; Sivakoff, Gregory R.

    2012-01-01

    Low-ionization (Mg II, Fe II, and Fe III) broad absorption line quasars (LoBALs) probe a relatively obscured quasar population and could be at an early evolutionary stage for quasars. We study the intrinsic fractions of LoBALs using the Sloan Digital Sky Survey (SDSS), Two Micron All Sky Survey, and Faint Images of the Radio Sky at Twenty cm survey. We find that the LoBAL fractions of the near-infrared (NIR) and radio samples are approximately 5-7 times higher than those measured in the optical sample. This suggests that the fractions measured in the NIR and radio bands are closer to the intrinsic fractions of the populations, and that the optical fractions are significantly biased due to obscuration effects, similar to high-ionization broad absorption line quasars (HiBALs). Considering a population of obscured quasars that do not enter the SDSS, which could have a much higher LoBAL fraction, we expect that the intrinsic fraction of LoBALs could be even higher. We also find that the LoBAL fractions decrease with increasing radio luminosities, again, similarly to HiBALs. In addition, we find evidence for increasing fractions of LoBALs toward higher NIR luminosities, especially for FeLoBALs with a fraction of ∼18% at M K s < -31 mag. This population of NIR-luminous LoBALs may be at an early evolutionary stage of quasar evolution. To interpret the data, we use a luminosity-dependent model for LoBALs that yields significantly better fits than those from a pure geometric model.

  17. Influence of 2,3-dimercaptosuccinic acid on gastrointestinal lead absorption and whole-body lead retention

    International Nuclear Information System (INIS)

    Kapoor, S.C.; Wielopolski, L.; Graziano, J.H.; LoIacono, N.J.

    1989-01-01

    2,3-Dimercaptosuccinic acid (DMSA) is a new orally active heavy metal chelator for the treatment of childhood Pb intoxication on an outpatient basis. The influence of DMSA, as well as other chelating agents, on gastrointestinal 203Pb absorption and whole-body 203 Pb retention was examined. Groups of Sprague-Dawley rats (230-260 g) were gavaged with a solution containing approximately 25 mg/kg Pb [as Pb(NO 3 )2] plus 15 microCi 203 Pb. Some groups were then immediately given 0.11 mmol/kg of either DMSA, CaNa2EDTA, D-penicillamine, or BAL by oral gavage, while other groups received the same drugs by ip injection. Control groups received solutions of the drug vehicles po or ip. Whole-body Pb retention and gastrointestinal Pb absorption (whole body retention + urinary Pb excretion) were significantly decreased in rats that received DMSA po. This finding implies that the use of DMSA to treat childhood lead intoxication on an outpatient basis is not associated with a risk for increased Pb absorption

  18. Volume fraction dependence of transient absorption signal and nonlinearities in metal nanocolloids

    International Nuclear Information System (INIS)

    Jayabalan, J; Singh, Asha; Khan, Salahuddin; Chari, Rama

    2013-01-01

    Electron–lattice thermalization dynamics in metal nanoparticles or in bulk metal is usually estimated by measuring the decay time of the change in transmission following an optical excitation. Such measurements can be performed in transient absorption geometry using a femtosecond laser. We find that for silver nanoplatelet/water colloids, the decay time of the transient absorption depends on the volume fraction of silver in water. By estimating the volume fraction dependence of nonlinearities in the same samples, we show that the variation in the measured decay time is due to pump-depletion effects present in the sample. The correct correction factor for taking into account pump-depletion effects in fifth- and higher-order nonlinearities is also presented. (paper)

  19. Absorption of plant-incorporated nuclear fuel cycle elements from the gastro-intestinal tract

    International Nuclear Information System (INIS)

    Sullivan, M.F.; Garland, T.R.; Cataldo, D.A.; Schreckhise, R.G.

    1979-01-01

    Soybean plants (Glycine max cv Williams) grown hydroponically on solutions containing ammonium pertechnetate ( 95 Tcsup(m)O - 4 ) were fed to rats (omnivores) and guinea pigs (herbivores). Absorption of plant-incorporated technetium was compared with absorption of inorganic 95 Tcsup(m) from a gavaged solution or with absorption of 95 Tcsup(m) added to non-radioactive soybean tissues. In a second study absorption of plutonium from alfalfa (Medicago sativa cv Ladak) grown on soil amended with either 238 Pu nitrate or 238 Pu-DTPA was compared with absorption of gavaged 238 Pu solutions and 238 Pu mixed with non-radioactive alfalfa. Incorporation of 95 Tcsup(m) into soybean tissues resulted in decreased absorption by both animal species. In contrast, incorporation of 238 Pu in alfalfa resulted in an increased absorption when compared with controls that were administered inorganic 238 Pu. These results suggest that organic binding may alter, in either direction, absorption of nuclear fuel cycle elements. (author)

  20. Influence of oxidation state on the absorption of plutonium from the gastrointestinal tract

    International Nuclear Information System (INIS)

    Sullivan, M.F.; Ryan, J.L.; Gorham, L.S.; McFadden, K.M.

    1979-01-01

    Rats and guinea pigs treated intragastrically with either IV- or VI-valent 238 Pu showed no appreciable difference in absorption. Nitric acid solutions of 239 Pu (pH 2) were also administered to fasted and fed rats. When an oxidant (K 2 Cr 2 O 7 ) was present in the solution gavaged to fasted rats, absorption increased 34-fold. However, when 239 Pu VI was administered to fed rats in the absence of dichromate, there was no appreciable difference between the absorption of 239 Pu VI and 239 Pu IV

  1. The influence of fasting and valence on the gastrointestinal absorption of plutonium in hamsters and rabbits

    International Nuclear Information System (INIS)

    Stather, J.W.; Harrison, J.D.; Smith, H.; Rodwell, P.; David, A.J.

    1980-01-01

    Plutonium ingested in contaminated food may be complexed to biological ligands in the food materials. Also, it is known that Pu in drinking water can exist as Pu(VI). A suggestion has been made, based on the results obtained by Weeks et al (Radiation Res., Vol. 4, 339,1956) that ingestion of Pu(VI) could mean that absorption of Pu would be substantially underestimated by using the value recommended by the ICRP. To further investigate the effect on absorption of both the oxidation state of ingested Pu and the nutritional state of the animal, Pu(IV) and Pu(VI) were administered to normally fed and fasted hamsters. The absorption of Pu(IV) was also measured in rabbits. Absorption of Pu in hamsters was not enhanced by prior oxidation to Pu(VI). However, increased absorption of both Pu(IV) and Pu(VI) was obtained in fasted animals. The results do not substantiate the high value for absorption of Pu(VI) obtained by Weeks et al, and support the value of 10sup(-2%) recommended by the ICRP for soluble forms of Pu. (author)

  2. Inhibition by natural dietary substances of gastrointestinal absorption of starch and sucrose in rats and pigs: 1. Acute studies.

    Science.gov (United States)

    Preuss, Harry G; Echard, Bobby; Bagchi, Debasis; Stohs, Sidney

    2007-08-06

    Rapid gastrointestinal absorption of refined carbohydrates (CHO) is linked to perturbed glucose-insulin metabolism that is, in turn, associated with many chronic health disorders. We assessed the ability of various natural substances, commonly referred to as "CHO blockers," to influence starch and sucrose absorption in vivo in ninety-six rats and two pigs. These natural enzyme inhibitors of amylase/sucrase reportedly lessen breakdown of starches and sucrose in the gastrointestinal tract, limiting their absorption. To estimate absorption, groups of nine SD rats were gavaged with water or water plus rice starch and/or sucrose; and circulating glucose was measured at timed intervals thereafter. For each variation in the protocol a total of at least nine different rats were studied with an equal number of internal controls on three different occasions. The pigs rapidly drank CHO and inhibitors in their drinking water. In rats, glucose elevations above baseline over four hours following rice starch challenge as estimated by area-under-curve (AUC) were 40%, 27%, and 85% of their internal control after ingesting bean extract, hibiscus extract, and l-arabinose respectively in addition to the rice starch. The former two were significantly different from control. L-Arabinose virtually eliminated the rising circulating glucose levels after sucrose challenge, whereas hibiscus and bean extracts were associated with lesser decreases than l-arabinose that were still significantly lower than control. The glucose elevations above baseline over four hours in rats receiving sucrose (AUC) were 51%, 43% and 2% of control for bean extract, hibiscus extract, and L-arabinose, respectively. Evidence for dose-response of bean and hibiscus extracts is reported. Giving the natural substances minus CHO challenge caused no significant changes in circulating glucose concentrations, indicating no major effects on overall metabolism. A formula combining these natural products significantly

  3. Time and angle resolved phonon absorption in the fractional quantum hall regime

    International Nuclear Information System (INIS)

    Devitt, A.M.

    2000-09-01

    The work described in this thesis is a study of the phonon absorption by a two-dimensional electron system (2DES) in the fractional quantum Hall regime and also at ν = 1/2. The fractional quantum Hall effect arises in 2DES's in high magnetic fields and is characterised by the quantisation of the transverse or Hall resistance and the vanishing longitudinal conductivity. The filling factor denotes the number of filled Landau levels and the quantum Hall effect occurs when this ratio is at certain rational odd denominator filling factors. The phenomenology of the effect arises due to the existence of an energy gap between the ground state and the lowest excited state. This energy gap is characterised by a deep minimum, or minima, at finite in-plane wavevector. Acoustic phonon absorption is expected to probe the energy gap at wavevectors close to or at the minimum in the dispersion curve. The experiments reported here incorporate the use of a thin film heater to produce a pulse of phonons of which a fraction are absorbed by the 2DES. A fast amplifier and signal averaging board enable detection of small signals due to absorption of phonons. The technique used allows time resolution of the phonon signal which typically takes place over a period of 10 μs or so. The time resolution enables different phonon modes to be studied. By altering the position of the heater relative to the 2DES angular resolution is also possible. The phonon absorption at several different filling factors has been investigated and the energy gaps found are in reasonable agreement with theoretical predictions. The absorption at ν 1/2 has also been investigated. Here the composite fermions are expected to have a well defined Fermi wavevector. The absorption at ν = 1/2 and the fractional quantum Hall states is found to be qualitatively and quantitatively different. We see that the change in electron temperature atν = 1/2 is much less than at ν = 1/3 due to the larger heat capacity. At ν = 1

  4. Species variability in the gastrointestinal absorption and distribution of soluble or insoluble compounds of plutonium

    International Nuclear Information System (INIS)

    Sullivan, M.F.; Gorham, L.S.; Blanton, E.F.

    1980-01-01

    Absorption of plutonium was measured after administration to neonatal rats, dogs, and swine by gavage or inhalation. The amount absorbed was not appreciably different for any of the three species, but absorption of the soluble nitrate form was 1000 times higher than that of the insoluble oxide. The higher quantities of 238 Pu absorbed and retained in the GI tract of swine suggested that solubilization of the oxide in the lung may have caused the increase. Studies with the more insoluble 239 PuO 2 also resulted in increased retention

  5. Optical Measurement of Radiocarbon below Unity Fraction Modern by Linear Absorption Spectroscopy.

    Science.gov (United States)

    Fleisher, Adam J; Long, David A; Liu, Qingnan; Gameson, Lyn; Hodges, Joseph T

    2017-09-21

    High-precision measurements of radiocarbon ( 14 C) near or below a fraction modern 14 C of 1 (F 14 C ≤ 1) are challenging and costly. An accurate, ultrasensitive linear absorption approach to detecting 14 C would provide a simple and robust benchtop alternative to off-site accelerator mass spectrometry facilities. Here we report the quantitative measurement of 14 C in gas-phase samples of CO 2 with F 14 C radiocarbon measurement science including the study of biofuels and bioplastics, illicitly traded specimens, bomb dating, and atmospheric transport.

  6. Fractional energy absorption from beta-emitting particles in the rat lung

    International Nuclear Information System (INIS)

    Snipes, M.B.

    1977-01-01

    Forty-four male, Fischer-344 rats were exposed nose-only to an aerosol of 144 Ce in fused aluminosilicate particles to obtain a relatively insoluble lung burden of this material. Twenty-eight rats, ages 12 to 25 weeks with body weights of 183 to 337 grams were analyzed seven to nine days after exposure; lung burdens were 13 to 82 nCi. An additional group of 16 rats was exposed when 12 weeks old and maintained for six months prior to analysis; body weights and lung burdens at six months after exposure ranged from 276 to 368 grams and 16 to 46 nCi, respectively. Lungs were analyzed, inflated and deflated in a 4π beta spectrometer to determine fractional energy absorption for 144 Ce. Over the relatively narrow range of sizes, 0.88 to 1.66 grams, for lungs in this study the average fractional energy absorption and its standard deviation was 0.23 +- 0.078 for the inflated lung and 0.40 +- 0.087 for the deflated lung

  7. Detection of gastrointestinal cancer by elastic scattering and absorption spectroscopies with the Los Alamos Optical Biopsy System

    Energy Technology Data Exchange (ETDEWEB)

    Mourant, J.R.; Boyer, J.; Johnson, T.M.; Lacey, J.; Bigio, I.J. [Los Alamos National Lab., NM (United States); Bohorfoush, A. [Wisconsin Medical School, Milwaukee, WI (United States). Dept. of Gastroenterology; Mellow, M. [Univ. of Oklahoma Medical School, Oklahoma City, OK (United States). Dept. of Gastroenterology

    1995-03-01

    The Los Alamos National Laboratory has continued the development of the Optical Biopsy System (OBS) for noninvasive, real-time in situ diagnosis of tissue pathologies. In proceedings of earlier SPIE conferences we reported on clinical measurements in the bladder, and we report here on recent results of clinical tests in the gastrointestinal tract. With the OBS, tissue pathologies are detected/diagnosed using spectral measurements of the elastic optical transport properties (scattering and absorption) of the tissue over a wide range of wavelengths. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, exhibit significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be wavelength dependent. Thus, morphology and size changes can be expected to cause significant changes m an optical signature that is derived from the wavelength-dependence of elastic scattering. Additionally, the optical geometry of the OBS beneficially enhances its sensitivity for measuring absorption bands. The OBS employs a small fiber-optic probe that is amenable to use with any endoscope or catheter, or to direct surface examination, as well as interstitial needle insertion. Data acquistion/display time is <1 second.

  8. A code for the calculation of self-absorption fractions of photons

    International Nuclear Information System (INIS)

    Jaegers, P.; Landsberger, S.

    1988-01-01

    Neutron activation analysis (NAA) is now a well-established technique used by many researchers and commercial companies. It is often wrongly assumed that these NAA methods are matrix independent over a wide variety of samples. Accuracy at the level of a few percent is often difficult to achieve, since components such as timing, pulse pile-up, high dead-time corrections, sample positioning, and chemical separations may severely compromise the results. One area that has received little attention is the calculation of the effect of self-absorption of gamma-rays (including low-energy ones) in samples, particularly those with major components of high-Z values. The analysis of trace components in lead samples is an obvious example, but other high-Z matrices such as various permutations and combinations of zinc, tin, lead, copper, silver, antimony, etc.; ore concentrates; and meteorites are also affected. The authors have developed a simple but effective personal-computer-compatible user-friendly code, however, which can calculate the amount of energy signal that is lost due to the presence of any amount of one or more Z components. The program is based on Dixon's paper of 1951 for the calculation of self-absorption corrections for linear, cylindrical, and spherical sources. To determine the self-absorption fraction of a photon in a source, the FORTRAN computer code SELFABS was written

  9. Effect of maturation on gastrointestinal absorption of epidermal growth factor in rats

    International Nuclear Information System (INIS)

    Thornburg, W.; Rao, R.K.; Matrisian, L.M.; Magun, B.E.; Koldovsky, O.

    1987-01-01

    Epidermal growth factor (EGF) was iodinated and administered orally to 13- to 15-day-old suckling rats and 29- to 31-day-old weanling rats. After 30 min, stomach, small intestine, plasma, liver, lung, and skin were removed. The tissues were homogenized and 125 I radioactivity was extracted. Compared with suckling rats, the delivery of total radioactivity into peripheral tissues was enhanced in skin of weanling rats and tended to be higher in plasma and liver. In contrast, there was a 3.3-fold reduction in radioactivity remaining in the intestinal wall. Sephadex G-25 chromatography of most samples, especially liver and intestinal wall, revealed a decrease in the proportion of intact 125 I-EGF eluting in the void volume. As a result, because the amount of total radioactivity also differed, the overall recovery of radioactivity of void volume 125 I-EGF was similar in both age groups except for an increase in skin and a decrease in the intestinal of weanling rats. Extracts of all tissues of weanling rats examined contained immunoreactive 125 I-EGF. Samples obtained from tissues and content of the gastrointestinal tract of both age groups bound specifically to A431 cell surface receptors. These results thus indicate that EGF is absorbed and delivered to various tissues of weanling rats. Nevertheless, quantitative and qualitative changes in these processes occur during the postnatal period

  10. Effect of pH and comedication on gastrointestinal absorption of posaconazole: monitoring of intraluminal and plasma drug concentrations.

    Science.gov (United States)

    Walravens, Jeroen; Brouwers, Joachim; Spriet, Isabel; Tack, Jan; Annaert, Pieter; Augustijns, Patrick

    2011-11-01

    Posaconazole (Noxafil®) is an extended-spectrum triazole antifungal agent for prevention and treatment of invasive fungal infections. An inadequate dietary intake and abnormal gastric pH levels are common in critically ill patients receiving antifungal treatment with posaconazole, resulting in unpredictable bioavailability and sub-therapeutic plasma concentrations. This study was carried out to elucidate the impact of pH on posaconazole absorption and to explore the underlying mechanisms of enhanced intestinal absorption when coadministering an acidic carbonated beverage. In contrast to previously published studies, in which only plasma concentrations were determined, we also explored the gastric and intestinal behaviour of posaconazole after a single oral dose. A crossover study was performed in five healthy subjects. A single dose (10 mL) of posaconazole suspension (40 mg/mL) was administered orally in four different conditions: with 330 mL of water (condition 1); with 330 mL of a cola beverage [Coca-Cola®] (condition 2); with 330 mL of water following intake of the proton pump inhibitor esomeprazole 40 mg once daily for 3 days (condition 3); or with 330 mL of Coca-Cola® following intake of esomeprazole 40 mg once daily for 3 days (condition 4). After administration, gastrointestinal fluid and plasma samples were collected at regular time points, and posaconazole concentrations were determined. Compared with administration with water, coadministration of Coca-Cola® did not alter the pH of the intraluminal environment but did significantly increase posaconazole gastric concentrations (+102%; p Coca-Cola® and prolonged gastric residence. Coadministration of esomeprazole led to an increased gastric pH, which was accompanied by decreased posaconazole absorption; the mean plasma and gastric area under the concentration-time curve (AUC) values decreased by 37% and 84%, respectively. Simultaneous intake of Coca-Cola® could not completely compensate for the

  11. Color-octet fraction in J/ψ production and absorption

    International Nuclear Information System (INIS)

    Wong, C.; Wong, C.W.

    1998-01-01

    The cross section between a c bar c pair and a nucleon is small and sensitive to the c-bar c separation if the pair is in a color-singlet state, but very large and insensitive to the separation if it is in a color-octet state. We use this property in an absorption model involving both color components to deduce the color structure of c bar c pairs produced in pA→ψX reactions. Our analysis shows that the NA3, NA38, and E772 data are not inconsistent with the theoretical picture that color-octet and color-singlet precursors are produced in roughly equal proportions if the produced color-singlet precursors are pointlike and transparent. However, if the color-singlet precursors are not transparent but have a cross section of a few mb, these data do show a definite preference for a larger fraction of color-singlet precursors. In either case, the color-octet fraction increases with x F , approaching close to unity as x F increases to about 0.5. copyright 1998 The American Physical Society

  12. Fractional Absorption of Active Absorbable Algal Calcium (AAACa and Calcium Carbonate Measured by a Dual Stable-Isotope Method

    Directory of Open Access Journals (Sweden)

    Steven A. Abrams

    2010-07-01

    Full Text Available With the use of stable isotopes, this study aimed to compare the bioavailability of active absorbable algal calcium (AAACa, obtained from oyster shell powder heated to a high temperature, with an additional heated seaweed component (Heated Algal Ingredient, HAI, with that of calcium carbonate. In 10 postmenopausal women volunteers aged 59 to 77 years (mean ± S.D., 67 ± 5.3, the fractional calcium absorption of AAACa and CaCO3 was measured by a dual stable isotope method. 44Ca-enriched CaCO3 and AAACa were administered in all subjects one month apart. After a fixed-menu breakfast and pre-test urine collection (Urine 0, 42Ca-enriched CaCl2 was intravenously injected, followed by oral administration of 44Ca-enriched CaCO3 without carrier 15 minutes later, and complete urine collection for the next 24 hours (Urine 24. The fractional calcium absorption was calculated as the ratio of Augmentation of 44Ca from Urine 0 to Urine 24/ augmentation of 42Ca from Urine 0 to Urine 24. Differences and changes of 44Ca and 42Ca were corrected by comparing each with 43Ca. Fractional absorption of AAACa (mean ± S.D., 23.1 ± 6.4, was distinctly and significantly higher than that of CaCO3 (14.7 ± 6.4; p = 0.0060 by paired t-test. The mean fractional absorption was approximately 1.57-times higher for AAACa than for CaCO3. The serum 25(OH vitamin D level was low (mean ± S.D., 14.2 ± 4.95 ng/ml, as is common in this age group in Japan. Among the parameters of the bone and mineral metabolism measured, none displayed a significant correlation with the fractional absorption of CaCO3 and AAACa. Higher fractional absorption of AAACa compared with CaCO3 supports previous reports on the more beneficial effect of AAACa than CaCO3 for osteoporosis.

  13. In Vivo Dissolution and Systemic Absorption of Immediate Release Ibuprofen in Human Gastrointestinal Tract under Fed and Fasted Conditions.

    Science.gov (United States)

    Koenigsknecht, Mark J; Baker, Jason R; Wen, Bo; Frances, Ann; Zhang, Huixia; Yu, Alex; Zhao, Ting; Tsume, Yasuhiro; Pai, Manjunath P; Bleske, Barry E; Zhang, Xinyuan; Lionberger, Robert; Lee, Allen; Amidon, Gordon L; Hasler, William L; Sun, Duxin

    2017-12-04

    In vivo drug dissolution in the gastrointestinal (GI) tract is largely unmeasured. The purpose of this clinical study was to evaluate the in vivo drug dissolution and systemic absorption of the BCS class IIa drug ibuprofen under fed and fasted conditions by direct sampling of stomach and small intestinal luminal content. Expanding current knowledge of drug dissolution in vivo will help to establish physiologically relevant in vitro models predictive of drug dissolution. A multilumen GI catheter was orally inserted into the GI tract of healthy human subjects. Subjects received a single oral dose of ibuprofen (800 mg tablet) with 250 mL of water under fasting and fed conditions. The GI catheter facilitated collection of GI fluid from the stomach, duodenum, and jejunum. Ibuprofen concentration in GI fluid supernatant and plasma was determined by LC-MS/MS. A total of 23 subjects completed the study, with 11 subjects returning for an additional study visit (a total of 34 completed study visits). The subjects were primarily white (61%) and male (65%) with an average age of 30 years. The subjects had a median [min, max] weight of 79 [52, 123] kg and body mass index of 25.7 [19.4, 37.7] kg/m 2 . Ibuprofen plasma levels were higher under fasted conditions and remained detectable for 28 h under both conditions. The AUC 0-24 and C max were lower in fed subjects vs fasted subjects, and T max was delayed in fed subjects vs fasted subjects. Ibuprofen was detected immediately after ingestion in the stomach under fasting and fed conditions until 7 h after dosing. Higher levels of ibuprofen were detected in the small intestine soon after dosing in fasted subjects compared to fed. In contrast to plasma drug concentration, overall gastric concentrations remained higher under fed conditions due to increased gastric pH vs fasting condition. The gastric pH increased to near neutrality after feedingbefore decreasing to acidic levels after 7 h. Induction of the fed state reduced systemic

  14. Gastrointestinal System

    NARCIS (Netherlands)

    Jepson, Mark A.; Bouwmeester, Hans

    2017-01-01

    The epithelial lining of the gastrointestinal tract (GIT) acts as a barrier to uptake of potentially dangerous material while allowing absorption of processed food. The gut may be exposed to a diverse range of engineered nanomaterials due to their deliberate addition to food and consumer products

  15. Prosopis juliflora Pods Alkaloid-rich Fraction: In vitro Anthelmintic Activity on Goat Gastrointestinal Parasites and Its Cytotoxicity on Vero Cells.

    Science.gov (United States)

    Lima, Helimar Gonçalves; Gomes, Danilo Cavalcante; Santos, Nathália Silva; Dias, Êuder Reis; Botura, Mariana Borges; Batatinha, Maria José Moreira; Branco, Alexsandro

    2017-10-01

    This study was designed to assess the in vitro anthelmintic activity of the fraction containing alkaloid from Prosopis juliflora pods on goat gastrointestinal nematodes using the egg hatch assay (EHA), larval migration inhibition assay (LMIA), and larval motility assay (LMA). The alkaloid-rich fraction (AF) - content juliprosopine as major alkaloid - was obtained from ethyl acetate extract after fractionation in Sephadex LH-20 chromatography column and its characterization were made by nuclear magnetic resonance analysis together with literature data comparison. The concentrations tested were 4.0, 2.67, 1.78, 1.19, and 0.79 mg/mL (EHA) and 4 mg/mL (LMIA and LMA). The in vitro cytotoxicity on Vero cell cultures was determined with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and trypan blue tests. High ovicidal activity was observed with IC 50 and IC 90 values at 1.1 and 1.43 mg/mL for AF. On the other hand, this fraction showed low larvicidal activity and high toxic effect. Thus, P. juliflora pod alkaloid rich-fraction has ovicidal activity in vitro against goat gastrointestinal nematodes and cytotoxic in Vero cell cultures. Prosopis juliflora alkaloid-rich fraction (AF) showed in vitro anthelmintic effect against gastrointestinal nematodes of goatsThe AF was more effective against eggs than third larval stage (L 3 ) of gastrointestinal nematodesThe AF showed cytotoxicity activity on Vero cell lineThe juliprosopine was the main alkaloid found in the AF from P. juliflora pods. Abbreviations used: AF: Alkaloid-rich fraction; DMSO: Dimethyl sulfoxide; EE: Ethyl acetate extract; EHA: Egg hatch assay; IC50: Inhibitory concentration 50%; IC90: Inhibitory concentration 90%; L3: Infective larvae; LMA: Larval motility assay; LMIA: Larval migration inhibition assay; MTT: Bromide 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; NMR: Nuclear magnetic resonance; PBS: Phosphate buffered saline; RPMI: Roswell Park Memorial Institute médium; TLC

  16. ABSORPTION-LINE SPECTROSCOPY OF GRAVITATIONALLY LENSED GALAXIES: FURTHER CONSTRAINTS ON THE ESCAPE FRACTION OF IONIZING PHOTONS AT HIGH REDSHIFT

    Energy Technology Data Exchange (ETDEWEB)

    Leethochawalit, Nicha; Ellis, Richard S.; Zitrin, Adi [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MS 249-17, Pasadena, CA 91125 (United States); Jones, Tucker A. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Stark, Daniel P. [Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States)

    2016-11-10

    The fraction of ionizing photons escaping from high-redshift star-forming galaxies is a key obstacle in evaluating whether galaxies were the primary agents of cosmic reionization. We previously proposed using the covering fraction of low-ionization gas, measured via deep absorption-line spectroscopy, as a proxy. We now present a significant update, sampling seven gravitationally lensed sources at 4 < z < 5. We show that the absorbing gas in our sources is spatially inhomogeneous, with a median covering fraction of 66%. Correcting for reddening according to a dust-in-cloud model, this implies an estimated absolute escape fraction of ≃19% ± 6%. With possible biases and uncertainties, collectively we find that the average escape fraction could be reduced to no less than 11%, excluding the effect of spatial variations. For one of our lensed sources, we have sufficient signal-to-noise ratio to demonstrate the presence of such spatial variations and scatter in its dependence on the Ly α equivalent width, consistent with recent simulations. If this source is typical, our lower limit to the escape fraction could be reduced by a further factor ≃2. Across our sample, we find a modest anticorrelation between the inferred escape fraction and the local star formation rate, consistent with a time delay between a burst and leaking Lyman continuum photons. Our analysis demonstrates considerable variations in the escape fraction, consistent with being governed by the small-scale behavior of star-forming regions, whose activities fluctuate over short timescales. This supports the suggestion that the escape fraction may increase toward the reionization era when star formation becomes more energetic and burst-like.

  17. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    International Nuclear Information System (INIS)

    Sun Min; Zhao Lixia; Guo Chenyu; Cao Fengliang; Chen Huanlei; Zhao Liyan; Tan Qi; Zhu Xiuqing; Zhu Fanping; Ding Tingting; Zhai Yingjie; Zhai Guangxi

    2012-01-01

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40–400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  18. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    Science.gov (United States)

    Sun, Min; Zhao, Lixia; Guo, Chenyu; Cao, Fengliang; Chen, Huanlei; Zhao, Liyan; Tan, Qi; Zhu, Xiuqing; Zhu, Fanping; Ding, Tingting; Zhai, Yingjie; Zhai, Guangxi

    2012-02-01

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40-400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  19. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sun Min; Zhao Lixia; Guo Chenyu; Cao Fengliang; Chen Huanlei; Zhao Liyan; Tan Qi; Zhu Xiuqing; Zhu Fanping; Ding Tingting; Zhai Yingjie; Zhai Guangxi, E-mail: professorzhai@yeah.net [Shandong University, Department of Pharmaceutics, College of Pharmacy (China)

    2012-02-15

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40-400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  20. Absorption of plutonium from the gastrointestinal tract of rats and guinea pigs after ingestion of alfalfa containing 238Pu

    International Nuclear Information System (INIS)

    Sullivan, M.F.; Garland, T.R.; Cataldo, D.A.; Wildung, R.E.; Drucker, H.

    1980-01-01

    The absorption of inorganic compounds of plutonium from the GI tract is so low that ingestion of this radionuclide does not appear to present a major health hazard. However, combining this actinide with organic compounds, such as chelating agents, can markedly increase absorption. Similarly, when Pu or other long-lived nuclides are released into the environment and incorporated into plants they may be complexed with naturally occurring organic ligands. It might then be possible for these nuclides to more effectively enter into the food chain. To test for this possibility, alfalfa was grown in the presence of inorganic plutonium, the plant tissue was fed to animals, and a comparison was made of the absorption from the gut of this plant-incorporated Pu relative to inorganic Pu. The results of these experiments, while not conclusive, do support the view that information is needed on food chain behavior of the actinide nuclear fuels as a precaution against exceeding dose limits. (author)

  1. Measurements of void fraction in a water-molten tin system by X-ray absorption

    International Nuclear Information System (INIS)

    Baker, Michael C.; Bonazza, Riccardo; Corradini, Michael L.

    1998-01-01

    A facility has been developed to study the explosive interactions of gas-water injection into a molten tin pool. The experimental apparatus allows for variable nitrogen gas and water injection into the base of a steel tank containing up to 25 kg of molten tin. Due to the opaque nature of the molten metal-gas-water mixture and steel tank, a visualization and measurement technique using continuous high energy x-rays had to be developed. Visualization of the multiphase mixture can be done at 220 Hz with 256x256 pixel resolution or at 30 Hz with 480x1128 pixel resolution. These images are stored digitally and subsequently processed to obtain two dimensional mappings of the chordal average void fraction in the mixture. The image processing method has been used to measure void fraction in experiments that did not include water in the injection mixture. This work includes a comparison to previous studies of integral void fraction data in pools of molten metal with gas injection. (author)

  2. Effect of Fiber Volume Fraction and Water Absorption toward Bending Strength of Coconut Filters/ Polyester Composite

    Directory of Open Access Journals (Sweden)

    I Putu Lokantara

    2012-11-01

    Full Text Available The variation of fibre volume and the duration of water soaking take influence on the mechanical properties of composite. This research aim is to know the influence of fraction volume fibre and soaking duration on the mineral watertoward the tensile strength and flexural of polyester-coconut-tapis composite. This research used coconut-tapis fibre which is cut 1 cm in length with 0%, 5%, 7,5%, and 10% fiber volume fraction, unsaturated-polyester (UPRs matrix resin type Yucalac 157 BQTN-EX, and MEKPO hardener. The flexure specimen are made by press hand lay-up method and cut according ASTM D790-03 for the flexure test. The result of flexure test shows that the duration of soaking and the fiber volume fraction give a significant effect on the flexural strength of composite. The highest strength are reached by composite with 10% fibre volume on 48 hour soaking time equal to 41.994 MPa. The flexure modulus happenend shows increasing until 24 hour soaking time. The highest modulus are reached by composite with 10% fibre volume equal to 7.114 GPa while the lowest are reached by composite with 0% fibre volume equal to 3,023 GPa.

  3. The impact of supersaturation level for oral absorption of BCS class IIb drugs, dipyridamole and ketoconazole, using in vivo predictive dissolution system: Gastrointestinal Simulator (GIS).

    Science.gov (United States)

    Tsume, Yasuhiro; Matsui, Kazuki; Searls, Amanda L; Takeuchi, Susumu; Amidon, Gregory E; Sun, Duxin; Amidon, Gordon L

    2017-05-01

    The development of formulations and the assessment of oral drug absorption for Biopharmaceutical Classification System (BCS) class IIb drugs is often a difficult issue due to the potential for supersaturation and precipitation in the gastrointestinal (GI) tract. The physiological environment in the GI tract largely influences in vivo drug dissolution rates of those drugs. Thus, those physiological factors should be incorporated into the in vitro system to better assess in vivo performance of BCS class IIb drugs. In order to predict oral bioperformance, an in vitro dissolution system with multiple compartments incorporating physiologically relevant factors would be expected to more accurately predict in vivo phenomena than a one-compartment dissolution system like USP Apparatus 2 because, for example, the pH change occurring in the human GI tract can be better replicated in a multi-compartmental platform. The Gastrointestinal Simulator (GIS) consists of three compartments, the gastric, duodenal and jejunal chambers, and is a practical in vitro dissolution apparatus to predict in vivo dissolution for oral dosage forms. This system can demonstrate supersaturation and precipitation and, therefore, has the potential to predict in vivo bioperformance of oral dosage forms where this phenomenon may occur. In this report, in vitro studies were performed with dipyridamole and ketoconazole to evaluate the precipitation rates and the relationship between the supersaturation levels and oral absorption of BCS class II weak base drugs. To evaluate the impact of observed supersaturation levels on oral absorption, a study utilizing the GIS in combination with mouse intestinal infusion was conducted. Supersaturation levels observed in the GIS enhanced dipyridamole and ketoconazole absorption in mouse, and a good correlation between their supersaturation levels and their concentration in plasma was observed. The GIS, therefore, appears to represent in vivo dissolution phenomena and

  4. The effect of x rays, DTPA, and aspirin on the absorption of plutonium from the gastrointestinal tract of rats

    International Nuclear Information System (INIS)

    Sullivan, M.F.; Gorham, L.S.; Miller, B.M.

    1983-01-01

    To measure the effect of radiation on plutonium transport, rats that were exposed to 250-kVp X rays were given 238 Pu 3 days afterwards by either gavage or injection into a ligated segment of the duodenum. In a second group of experiments, rats were either injected intraduodenally with 238 Pu-DTPA or administered the chelate intravenously and the 238 Pu by gavage. In a third experiment, rats that had been gavaged with 200 or 400 mg/kg/day of aspirin for 2 days were injected intragastrically with 238 Pu nitrate. Results of the first experiment showed a dose-dependent increase in 238 Pu absorption between 800 and 1500 rad of lower-body X irradiation. Intravenous or intraduodenal injections of DTPA caused a marked increase in 238 Pu absorption but resulted in decreased plutonium deposition in the skeleton and liver. Retention of 238 Pu in the skeleton of rats given aspirin was double that of controls, but the effect on plutonium absorption was less marked than that of DTPA

  5. Blocking carbohydrate absorption and weight loss: a clinical trial using a proprietary fractionated white bean extract.

    Science.gov (United States)

    Udani, Jay; Singh, Betsy B

    2007-01-01

    A proprietary fractionated white bean extract of Phaseolus vulgaris has been shown in vitro to inhibit the digestive enzyme alpha-amylase. This may prevent or delay the digestion of complex carbohydrates, potentially resulting in weight loss. A 4-week randomized, double-blind, placebo-controlled study of 25 healthy subjects consuming 1000 mg of a proprietary fractioned white bean extract or an identical placebo twice a day before meals in conjunction with a multi-component weight-loss program, including diet, exercise, and behavioral intervention, was conducted. Both groups reduced their weight and waist size significantly from baseline. The active group lost 6.0 lbs (P=.0002) and 2.2 in (P=.0050), and the placebo group lost 4.7 lbs (P=.0016) and 2.1 in (P=.0001). The differences between groups were not significant (weight P=.4235, waist size P=.8654). Through subsequent exploratory analysis to investigate group findings further, subjects were stratified by total dietary carbohydrate intake. This probative analysis revealed that the tertile of subjects who had consumed the most carbohydrates demonstrated significant reductions in both weight (8.7 lbs vs 1.7 lbs, P=.0412) and waist size (3.3 in vs 1.3 in P=.0100) compared with placebo subjects in the same tertile of carbohydrate intake. Subjects who adhere to a program including dietary modification, exercise, and behavioral intervention can significantly reduce their weight and waist size in a short period of time. In an exploratory analysis of data, the tertile of subjects who ate the most carbohydrates experienced a significant reduction in both weight and waist size with the addition of the white bean extract compared to the placebo group of the same tertile of carbohydrate consumption. Longer studies with a larger pool of subjects are required to validate these findings.

  6. Risk assessment of excess drug and sunscreen absorption via skin with ablative fractional laser resurfacing : optimization of the applied dose for postoperative care.

    Science.gov (United States)

    Chen, Wei-Yu; Fang, Chia-Lang; Al-Suwayeh, Saleh A; Yang, Hung-Hsu; Li, Yi-Ching; Fang, Jia-You

    2013-09-01

    The ablative fractional laser is a new modality used for surgical resurfacing. It is expected that laser treatment can generally deliver drugs into and across the skin, which is toxicologically relevant. The aim of this study was to establish skin absorption characteristics of antibiotics, sunscreens, and macromolecules via laser-treated skin and during postoperative periods. Nude mice were employed as the animal model. The skin received a single irradiation of a fractional CO2 laser, using fluences of 4-10 mJ with spot densities of 100-400 spots/cm(2). In vitro skin permeation using Franz cells was performed. Levels of skin water loss and erythema were evaluated, and histological examinations with staining by hematoxylin and eosin, cyclooxygenase-2, and claudin-1 were carried out. Significant signs of erythema, edema, and scaling of the skin treated with the fractional laser were evident. Inflammatory infiltration and a reduction in tight junctions were also observed. Laser treatment at 6 mJ increased tetracycline and tretinoin fluxes by 70- and 9-fold, respectively. A higher fluence resulted in a greater tetracycline flux, but lower skin deposition. On the other hand, tretinoin skin deposition increased following an increase in the laser fluence. The fractional laser exhibited a negligible effect on modulating oxybenzone absorption. Dextrans with molecular weights of 4 and 10 kDa showed increased fluxes from 0.05 to 11.05 and 38.54 μg/cm(2)/h, respectively. The optimized drug dose for skin treated with the fractional laser was 1/70-1/60 of the regular dose. The skin histology and drug absorption had recovered to a normal status within 2-3 days. Our findings provide the first report on risk assessment of excessive skin absorption after fractional laser resurfacing.

  7. Effects of Fat and Protein Preloads on Pouch Emptying, Intestinal Transit, Glycaemia, Gut Hormones, Glucose Absorption, Blood Pressure and Gastrointestinal Symptoms After Roux-en-Y Gastric Bypass.

    Science.gov (United States)

    Nguyen, Nam Q; Debreceni, Tamara L; Burgstad, Carly M; Neo, Melissa; Bellon, Max; Wishart, Judith M; Standfield, Scott; Bartholomeusz, Dylan; Rayner, Chris K; Wittert, Gary; Horowitz, Michael

    2016-01-01

    The aim was to determine the effects of fat and protein preloads on pouch emptying (PE), caecal arrival time (CAT), glucose absorption, blood glucose (BSL), gut hormones, haemodynamics and gastrointestinal (GI) symptoms in subjects who had undergone Roux-en-Y gastric bypass (RYGB) >12 months previously. Ten RYGB subjects were studied on three occasions, in randomised order, receiving 200-ml preloads of either water, fat (30 ml olive oil) or whey protein (55 g), 30 min before a mixed meal. PE, CAT, BSL, plasma 3-O-methyl-D-glucopyranose (3-OMG), insulin, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1) and glucagon, blood pressure (BP), heart rate (HR) and GI symptoms were assessed over 270 min. Although fat and protein preloads did not alter PE of either solids or liquids, the CAT of solids, but not liquids, was longer than that after the water preload (fat 68 ± 5 min and protein 71 ± 6 min vs. water 46 ± 5 min; P = 0.02). BSL elevated promptly after the meal on all days (P area under the curve (AUC(0-75 min)), 18.7 ± 18.2 vs. 107.2 ± 30.4 and 76.1 ± 19.3 mmol/L/min; P < 0.05). Compared to water preload, the protein and fat preloads were associated with greater increases in plasma insulin, GLP-1 and glucagon concentrations, a reduction in BP, and greater increases in HR, fullness, bloating and nausea. Plasma 3-OMG levels were lower after the protein than after the water and fat preloads (P < 0.001). Given its effects to attenuate post-prandial glycaemia, reduce intestinal glucose absorption and potentiate the "incretin response", without inducing more adverse post-prandial GI symptom, protein preload may prove clinically useful in RYGB patients and warrant further evaluation, particularly in those with type 2 diabetes (T2DM) and/or dumping syndrome.

  8. The effect of several crude oils and some petroleum distillation fractions on intestinal absorption in ducklings (Anas platyhynchos).

    Science.gov (United States)

    Crocker, A D; Cronshaw, J; Holmes, W N

    1975-01-01

    Ducklings given hypertonic saline drinking water show significant increases in the rates of Na+ and water transfer across the intestinal mucosa. These increased rates of transfer are maintained as long as the birds are fed dypertonic saline. Oral administration of a single small dose of crude oil had no effect on the basal rate of mucosal transfer in freshwater-maintained ducklings but the adaptive response of the mucosa is suppressed in birds given hypertonic saline. When crude oils from eight different geographical locations were tested, the degree of inhibition varied between them; the greatest and smallest degrees of inhibition being observed following administration of Kuwait and North Slope, Alaska, crude oils respectively. The effects of distallation fractions derived from two chemically different crude oils were also examined. The volume of each distallation fraction administered corresponded to its relative abundance in the crude oil from which it was derived. The inhibitory effect was not associated exclusively with the same distallation fractions from each oil. A highly naphthenic crude oil from the San Joaquin Valley, California, showed the greatest inhibitory activity in the least abundant (2%), low boiling point (smaller than 245 degrees C) fraction and the least inhibitory activity in the highest boiling point (greater than 482 degrees C) most abundant (47%) fraction. In contrast, a highly paraffinic crude oil from Paradox Basin, Utah, showed the greatest inhibitory effect with the highest boiling point fraction and a minimal effect with the lowest boiling point fraction; the relative abundances of these two fractions in the crude oil represented 27 and 28% respectively. Water-soluble extracts of both crude oils also had inhibitory effects on mucosal transfer rates and these roughly proportionate to the inhibitory potency of the low boiling point fraction of each oil. Weathered samples of San Joaquin Valley, California, and the Paradox Basin, Utah

  9. Speciation of copper and zinc in size-fractionated atmospheric particulate matter using total reflection mode X-ray absorption near-edge structure spectrometry

    International Nuclear Information System (INIS)

    Osan, Janos; Meirer, Florian; Groma, Veronika; Toeroek, Szabina; Ingerle, Dieter; Streli, Christina; Pepponi, Giancarlo

    2010-01-01

    The health effects of aerosol depend on the size distribution and the chemical composition of the particles. Heavy metals of anthropogenic origin are bound to the fine aerosol fraction (PM 2.5 ). The composition and speciation of aerosol particles can be variable in time, due to the time-dependence of anthropogenic sources as well as meteorological conditions. Synchrotron-radiation total reflection X-ray fluorescence (SR-TXRF) provides very high sensitivity for characterization of atmospheric particulate matter. X-ray absorption near-edge structure (XANES) spectrometry in conjunction with TXRF detection can deliver speciation information on heavy metals in aerosol particles collected directly on the reflector surface. The suitability of TXRF-XANES for copper and zinc speciation in size-fractionated atmospheric particulate matter from a short sampling period is presented. For high size resolution analysis, atmospheric aerosol particles were collected at different urban and rural locations using a 7-stage May cascade impactor having adapted for sampling on Si wafers. The thin stripe geometry formed by the particulate matter deposited on the May-impactor plates is ideally suited to SR-TXRF. Capabilities of the combination of the May-impactor sampling and TXRF-XANES measurements at HASYLAB Beamline L to Cu and Zn speciation in size-fractionated atmospheric particulate matter are demonstrated. Information on Cu and Zn speciation could be performed for elemental concentrations as low as 140 pg/m 3 . The Cu and Zn speciation in the different size fraction was found to be very distinctive for samples of different origin. Zn and Cu chemical state typical for soils was detected only in the largest particles studied (2-4 μm fraction). The fine particles, however, contained the metals of interest in the sulfate and nitrate forms.

  10. Determination of the elemental composition of cyanobacteria cells and cell fractions by atomic emission and atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Sedykh, Eh.M.; Lyabusheva, O.A.; Bannykh, L.N.; Tambiev, A.Kh.

    2005-01-01

    An approach to studying the elemental composition of cyanobacteria Spirulina platensis and Nostoc commune using a set of complementary analytical methods (ICP-AES, PAAS, and ETAAS) was proposed . The procedures were adapted for the determination of macro- and microelements (Na, K, Mg, Ca, Fe, Mn, Cu, Mo, Zn, B, and Se) in the biomass of cyanobacteria and separated cell fractions (chloroform and water-methanol extracts and precipitates). The conditions for the mineralization of biological materials were optimized for autoclave and microwave sample preparation procedures. The evaporation and atomization of Se and Mo in a graphite furnace in the presence of chloroform and methanol were studied [ru

  11. [Variation in soil Mn fractions as affected by long-term manure amendment using atomic absorption spectrophotometer in a typical grassland of inner Mongolia].

    Science.gov (United States)

    Fu, Ming-ming; Jiang, Yong; Bai, Yong-fei; Zhang, Yu-ge; Xu, Zhu-wen; Li, Bo

    2012-08-01

    The effect of sheep manure amendment on soil manganese fractions was conducted in a 11 year experiment at inner Mongolia grassland, using sequential extraction procedure in modified Community Bureau of Reference, and determined by atomic absorption spectrophotometer. Five treatments with dry sheep manure addition rate 0, 50, 250, 750, and 1500 g x m(-2) x yr(-1), respectively, were carried out in this experiment. Results showed that the recovery rate for total Mn was 91.4%-105.9%, as the percentage recovered from the summation of the improved BCR results with aqua regia extractable contents, and it was 97.2%-102.9% from certified soil reference materials. Plant available exchangeable Mn could be enhanced by 47.89%, but reducible and total Mn contents decreased significantly under heavy application of manure at depth of 0-5 cm. The effect of manure amendment on Mn fractions was greater in 0-5 cm than in 5-10 cm soil layer. The results are benefit to micronutrient fractions determination and nutrient management in grassland soils.

  12. Tunable diode laser absorption spectroscopy-based tomography system for on-line monitoring of two-dimensional distributions of temperature and H2O mole fraction

    International Nuclear Information System (INIS)

    Xu, Lijun; Liu, Chang; Jing, Wenyang; Cao, Zhang; Xue, Xin; Lin, Yuzhen

    2016-01-01

    To monitor two-dimensional (2D) distributions of temperature and H 2 O mole fraction, an on-line tomography system based on tunable diode laser absorption spectroscopy (TDLAS) was developed. To the best of the authors’ knowledge, this is the first report on a multi-view TDLAS-based system for simultaneous tomographic visualization of temperature and H 2 O mole fraction in real time. The system consists of two distributed feedback (DFB) laser diodes, a tomographic sensor, electronic circuits, and a computer. The central frequencies of the two DFB laser diodes are at 7444.36 cm −1 (1343.3 nm) and 7185.6 cm −1 (1391.67 nm), respectively. The tomographic sensor is used to generate fan-beam illumination from five views and to produce 60 ray measurements. The electronic circuits not only provide stable temperature and precise current controlling signals for the laser diodes but also can accurately sample the transmitted laser intensities and extract integrated absorbances in real time. Finally, the integrated absorbances are transferred to the computer, in which the 2D distributions of temperature and H 2 O mole fraction are reconstructed by using a modified Landweber algorithm. In the experiments, the TDLAS-based tomography system was validated by using asymmetric premixed flames with fixed and time-varying equivalent ratios, respectively. The results demonstrate that the system is able to reconstruct the profiles of the 2D distributions of temperature and H 2 O mole fraction of the flame and effectively capture the dynamics of the combustion process, which exhibits good potential for flame monitoring and on-line combustion diagnosis

  13. Organic palladium and palladium-magnesium chemical modifiers in direct determination of lead in fractions from distillation of crude oil by electrothermal atomic absorption analysis

    Science.gov (United States)

    Kowalewska, Zofia; Bulska, Ewa; Hulanicki, Adam

    1999-05-01

    Platinum reforming catalysts are easily poisoned by increased levels of lead, therefore a sensitive atomic absorption spectrometric procedure for lead determination in fractions from crude oil distillation was developed. Lead was present in organic form in the samples analysed therefore the behaviour of various lead compounds (Pb-alkylarylsulphonate, Pb-4-cyclohexanobutyrate, tetraethyllead, Pb in fuel oil) was studied. The best procedure for the determination of lead in different petroleum products, including those containing asphaltenes includes a pretreatment with iodine and methyltrioctylammonium chloride, followed by the use of an organic Pd-Mg modifier. Under these conditions an effective matrix removal is possible at a pyrolysis temperature up to approximately 1100°C and the behaviour of lead present in different forms is unified. The characteristic mass is 11-12 pg Pb, corresponding to a detection limit of 0.25 ng g -1 for 20 μl sample solution. This can be lowered by multiple injection.

  14. Gastrointestinal tuberculosis.

    Science.gov (United States)

    Galloway, D J; Scott, R N

    1986-10-01

    In the developed countries gastrointestinal tuberculosis is no longer common in clinical practice. In this setting the importance of the condition lies in the vagaries of its presentation and the fact that it is eminently treatable, usually by a combination of chemotherapy and surgery. The clinical features and complications of gastrointestinal tuberculosis are highlighted by the seven cases which we report. Diagnosis and treatment of this condition is discussed and attention is drawn to the importance of case notification. Clinicians should bear in mind the diagnosis of gastrointestinal tuberculosis when dealing with any patient with non-specific abdominal symptoms.

  15. Gastrointestinal bleeding

    Science.gov (United States)

    ... Sigmoidoscopy Alternative Names Lower GI bleeding; GI bleeding; Upper GI bleeding; Hematochezia Images GI bleeding - series Fecal occult blood test References Kovacs TO, Jensen DM. Gastrointestinal hemorrhage. In: Goldman L, Schafer AI, eds. Goldman- ...

  16. Low Buffer Capacity and Alternating Motility along the Human Gastrointestinal Tract: Implications for in Vivo Dissolution and Absorption of Ionizable Drugs.

    Science.gov (United States)

    Hens, Bart; Tsume, Yasuhiro; Bermejo, Marival; Paixao, Paulo; Koenigsknecht, Mark J; Baker, Jason R; Hasler, William L; Lionberger, Robert; Fan, Jianghong; Dickens, Joseph; Shedden, Kerby; Wen, Bo; Wysocki, Jeffrey; Loebenberg, Raimar; Lee, Allen; Frances, Ann; Amidon, Greg; Yu, Alex; Benninghoff, Gail; Salehi, Niloufar; Talattof, Arjang; Sun, Duxin; Amidon, Gordon L

    2017-12-04

    In this study, we determined the pH and buffer capacity of human gastrointestinal (GI) fluids (aspirated from the stomach, duodenum, proximal jejunum, and mid/distal jejunum) as a function of time, from 37 healthy subjects after oral administration of an 800 mg immediate-release tablet of ibuprofen (reference listed drug; RLD) under typical prescribed bioequivalence (BE) study protocol conditions in both fasted and fed states (simulated by ingestion of a liquid meal). Simultaneously, motility was continuously monitored using water-perfused manometry. The time to appearance of phase III contractions (i.e., housekeeper wave) was monitored following administration of the ibuprofen tablet. Our results clearly demonstrated the dynamic change in pH as a function of time and, most significantly, the extremely low buffer capacity along the GI tract. The buffer capacity on average was 2.26 μmol/mL/ΔpH in fasted state (range: 0.26 and 6.32 μmol/mL/ΔpH) and 2.66 μmol/mL/ΔpH in fed state (range: 0.78 and 5.98 μmol/mL/ΔpH) throughout the entire upper GI tract (stomach, duodenum, and proximal and mid/distal jejunum). The implication of this very low buffer capacity of the human GI tract is profound for the oral delivery of both acidic and basic active pharmaceutical ingredients (APIs). An in vivo predictive dissolution method would require not only a bicarbonate buffer but also, more significantly, a low buffer capacity of dissolution media to reflect in vivo dissolution conditions.

  17. Effect of pea and faba bean fractions on net fluid absorption in ETEC-infected small intestinal segements of weaned piglets

    NARCIS (Netherlands)

    Meulen, van der J.; Jansman, A.J.M.

    2010-01-01

    After weaning piglets frequently have diarrhoea associated with an enterotoxigenic Escherichia coli (ETEC) infection. Alternative plant protein sources such as peas, faba beans and lupins may contribute in preventing gastrointestinal problems. In the small intestinal segment perfusion model, the

  18. Adding glucose to food and solutions to enhance fructose absorption is not effective in preventing fructose-induced functional gastrointestinal symptoms: randomised controlled trials in patients with fructose malabsorption.

    Science.gov (United States)

    Tuck, C J; Ross, L A; Gibson, P R; Barrett, J S; Muir, J G

    2017-02-01

    In healthy individuals, the absorption of fructose in excess of glucose in solution is enhanced by the addition of glucose. The present study aimed to assess the effects of glucose addition to fructose or fructans on absorption patterns and genesis of gastrointestinal symptoms in patients with functional bowel disorders. Randomised, blinded, cross-over studies were performed in healthy subjects and functional bowel disorder patients with fructose malabsorption. The area-under-the-curve (AUC) was determined for breath hydrogen and symptom responses to: (i) six sugar solutions (fructose in solution) (glucose; sucrose; fructose; fructose + glucose; fructan; fructan + glucose) and (ii) whole foods (fructose in foods) containing fructose in excess of glucose given with and without additional glucose. Intake of fermentable short chain carbohydrates (FODMAPs; fermentable, oligo-, di-, monosaccharides and polyols) was controlled. For the fructose in solution study, in 26 patients with functional bowel disorders, breath hydrogen was reduced after glucose was added to fructose compared to fructose alone [mean (SD) AUC 92 (107) versus 859 (980) ppm 4 h -1 , respectively; P = 0.034). Glucose had no effect on breath hydrogen response to fructans (P = 1.000). The six healthy controls showed breath hydrogen patterns similar to those with functional bowel disorders. No differences in symptoms were experienced with the addition of glucose, except more nausea when glucose was added to fructose (P = 0.049). In the fructose in foods study, glucose addition to whole foods containing fructose in excess of glucose in nine patients with functional bowel disorders and nine healthy controls had no significant effect on breath hydrogen production or symptom response. The absence of a favourable response on symptoms does not support the concomitant intake of glucose with foods high in either fructose or fructans in patients with functional bowel disorders. © 2016 The British Dietetic

  19. Application of UV-visible absorption spectroscopy combined with two-dimensional correlation for insight into DOM fractions from native halophyte soils in a larger estuarine delta.

    Science.gov (United States)

    Wei, Huaibin; Yu, Huibin; Pan, Hongwei; Gao, Hongjie

    2018-05-01

    UV-visible absorption spectroscopy combined with principal component analysis (PCA) and two-dimensional correlation (2D correlation) is used to trace components of dissolved organic matter (DOM) extracted from soils in a larger estuarine delta and to investigate spatial variations of DOM fractions. Soil samples of different depths were collected from native halophyte soils along a saline gradient, i.e., Suaeda salsa Comm. (SSC), Chenopodium album Comm. (CAC), Phragmites australis Comm. (PAC), and Artemisia selengensis Comm. (ASC). Molecular weights of DOM within the SSC soil profile were the lowest, followed by the CAC, PAC, and ASC soil profiles. Humification degree of DOM within the ASC soil profile was the highest, followed by the PAC, SSC, and CAC soil profiles. DOM within the soil profiles mainly contained phenolic, carboxylic, microbial products, and aromatic and alkyl groups through the PCA, which presented the significant differentiation among the four native halophyte soil profiles. The 2D UV correlation spectra of DOM within the SSC soil profile indicated that the variations of the phenolic groups were the largest, followed by the carboxylic groups, microbial products, and humified organic materials according to the band changing order of 285 → 365 → 425 → 520 nm. The 2D UV correlation spectra of DOM within the CAC soil profiles determined that the decreasing order of the variations was phenolic groups > carboxylic groups > microbial products according the band changing order of 285 → 365 → 425 nm. The 2D UV correlation spectra of DOM within the PAC soil profile proved that the variations of the phenolic groups were larger than those of the carboxylic groups according to the band changing order of 285 → 365 nm. The 2D UV correlation spectra of DOM within the ASC soil profile demonstrated that the variations of the phenolic groups were larger than those of the other DOM fractions according to the broad cross-peak at

  20. Proposals for setting possible limits on intake of transuranium radionuclides absorbed from the gastrointestinal tract

    International Nuclear Information System (INIS)

    Zalikin, G.A.; Nisimov, P.G.

    1987-01-01

    The absorption of transuranium elements ( 238 Pu, 241 Am, 252 Cf) from the gastrointestinal (GI) tract as influenced by physiological factors (e.g. age) and physical and chemical properties of compounds incorporated has been studied in 600 white mongrel rats. Average values of absorption have been determined for simple salts and a complex citrate. A number of factors increasing absorption have been found. Thus, originally bound compounds contained in the meat of animals incorporated with 238 Pu and 241 Am when alive, 241 Am-containing potato juice and green oat stalks enhanced absorption by a factor of 5 to 30 as compared with an adequate control. Ethanol administered orally as a 20% solution increased the absorption of americium nitrate by 60% and that of citrate by 23%. Oral administratio of 241 Am nitrate solution together with ferric chloride changes the metabolic kinetics of the nuclide completely. The total absorption of americium from DI tract is 7.1 times that of the control, but a considerable fraction absorbed into blood is excreted with urine (4.2% over 8 days). Among physiological factors age effects the absorption of transuranics from the GI tract to acertain degree. The absorption of 252 Cf in 7 day-old young rats proves to be 8.1 times that of adults. Gestation brought about a 2.7 fold increase of 241 Am absorption

  1. gastrointestinal tract

    Directory of Open Access Journals (Sweden)

    Rolandas Vaicekauskas

    2016-07-01

    Full Text Available Introduction : Accurate diagnosis of subepithelial lesions (SELs in the gastrointestinal tract depends on a variety of methods: endoscopy, endoscopic ultrasound and different types of biopsy. Making an error-free diagnosis is vital for the subsequent application of an appropriate treatment. Aim: To evaluate the efficacy of deep biopsy via the endoscopic submucosal dissection (ESD technique for SELs in the upper gastrointestinal tract. Material and methods: It was a case series study. Deep biopsy via the ESD technique was completed in 38 patients between November 2012 and October 2014. Thirty-eight SELs in the upper gastrointestinal tract of varying size (very small ≤ 1 cm, small 1–2 cm and large ≥ 2 cm by means of the ESD technique after an incision with an electrosurgical knife of the overlying layers and revealing a small part of the lesion were biopsied under direct endoscopic view. Results: Deep biopsy via the ESD technique was diagnostic in 28 of 38 patients (73.3%; 95% CI: 59.7–89.7%. The diagnostic yield for SELs with a clear endophytic shape increased to 91.3%. An evident endophytic appearance of a subepithelial lesion, the mean number of biopsied samples (6.65 ±1.36 and the total size in length of all samples per case (19.88 ±8.07 mm were the main criteria influencing the positiveness of deep biopsy in the diagnostic group compared to the nondiagnostic one (p = 0.001; p = 0.025; p = 0.008. Conclusions : Deep biopsy via the ESD technique is an effective and safe method for the diagnosis of SELs especially with a clear endophytic appearance in a large number of biopsied samples.

  2. Sucralfate reduces the gastrointestinal absorption of norfloxacin.

    OpenAIRE

    Parpia, S H; Nix, D E; Hejmanowski, L G; Goldstein, H R; Wilton, J H; Schentag, J J

    1989-01-01

    The effect of sucralfate on the bioavailability of norfloxacin after single 400-mg doses of norfloxacin was evaluated in eight healthy males. Subjects received each of the following treatments in random sequence: (i), norfloxacin, 400 mg alone; (ii) sucralfate, 1 g, concurrently with norfloxacin, 400 mg; and (iii) sucralfate, 1 g, followed by norfloxacin, 400 mg, 2 h later. One day before administration of treatments 2 and 3, 1 g of sucralfate was given at 7 a.m., 11 a.m., 5 p.m., and 10 p.m....

  3. Gastrointestinal Traumatic Injuries: Gastrointestinal Perforation.

    Science.gov (United States)

    Revell, Maria A; Pugh, Marcia A; McGhee, Melanie

    2018-03-01

    The abdomen is a big place even in a small person. Gastrointestinal trauma can result in injury to the stomach, small bowel, colon, or rectum. Traumatic causes include blunt or penetrating trauma, such as gunshot wounds, stabbings, motor vehicle collisions, and crush injuries. Nontraumatic causes include appendicitis, Crohn disease, cancer, diverticulitis, ulcerative colitis, blockage of the bowel, and chemotherapy. The mechanism of injury will affect both the nature and severity of any resulting injuries. Treatment must address the critical and emergent nature of these injuries as well as issues that affect all trauma situations, which include management of hemodynamic instability. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. In Rwandese Women with Low Iron Status, Iron Absorption from Low-Phytic Acid Beans and Biofortified Beans Is Comparable, but Low-Phytic Acid Beans Cause Adverse Gastrointestinal Symptoms.

    Science.gov (United States)

    Petry, Nicolai; Rohner, Fabian; Gahutu, Jean Bosco; Campion, Bruno; Boy, Erick; Tugirimana, Pierrot L; Zimmerman, Michael Bruce; Zwahlen, Christian; Wirth, James P; Moretti, Diego

    2016-05-01

    Phytic acid (PA) is a major inhibitor of iron bioavailability from beans, and high PA concentrations might limit the positive effect of biofortified beans (BBs) on iron status. Low-phytic acid (lpa) bean varieties could increase iron bioavailability. We set out to test whether lpa beans provide more bioavailable iron than a BB variety when served as part of a composite meal in a bean-consuming population with low iron status. Dietary iron absorption from lpa, iron-biofortified, and control beans (CBs) (regular iron and PA concentrations) was compared in 25 nonpregnant young women with low iron status with the use of a multiple-meal crossover design. Iron absorption was measured with stable iron isotopes. PA concentration in lpa beans was ∼10% of BBs and CBs, and iron concentration in BBs was ∼2- and 1.5-fold compared with CBs and lpa beans, respectively. Fractional iron absorption from lpa beans [8.6% (95% CI: 4.8%, 15.5%)], BBs [7.3% (95% CI: 4.0%, 13.4%)], and CBs [8.0% (95% CI: 4.4%, 14.6%)] did not significantly differ. The total amount of iron absorbed from lpa beans and BBs was 421 μg (95% CI: 234, 756 μg) and 431 μg (95% CI: 237, 786 μg), respectively, and did not significantly differ, but was >50% higher (P beans were hard to cook, and their consumption caused transient adverse digestive side effects in ∼95% of participants. Gel electrophoresis analysis showed phytohemagglutinin L (PHA-L) residues in cooked lpa beans. BBs and lpa beans provided more bioavailable iron than control beans and could reduce dietary iron deficiency. Digestive side effects of lpa beans were likely caused by PHA-L, but it is unclear to what extent the associated digestive problems reduced iron bioavailability. This trial was registered at clinicaltrials.gov as NCT02215278. © 2016 American Society for Nutrition.

  5. Calcium absorption and achlorhydria

    International Nuclear Information System (INIS)

    Recker, R.R.

    1985-01-01

    Defective absorption of calcium has been thought to exist in patients with achlorhydria. The author compared absorption of calcium in its carbonate form with that in a pH-adjusted citrate form in a group of 11 fasting patients with achlorhydria and in 9 fasting normal subjects. Fractional calcium absorption was measured by a modified double-isotope procedure with 0.25 g of calcium used as the carrier. Mean calcium absorption (+/- S.D.) in the patients with achlorhydria was 0.452 +/- 0.125 for citrate and 0.042 +/- 0.021 for carbonate (P less than 0.0001). Fractional calcium absorption in the normal subjects was 0.243 +/- 0.049 for citrate and 0.225 +/- 0.108 for carbonate (not significant). Absorption of calcium from carbonate in patients with achlorhydria was significantly lower than in the normal subjects and was lower than absorption from citrate in either group; absorption from citrate in those with achlorhydria was significantly higher than in the normal subjects, as well as higher than absorption from carbonate in either group. Administration of calcium carbonate as part of a normal breakfast resulted in completely normal absorption in the achlorhydric subjects. These results indicate that calcium absorption from carbonate is impaired in achlorhydria under fasting conditions. Since achlorhydria is common in older persons, calcium carbonate may not be the ideal dietary supplement

  6. Gastrointestinal tract

    International Nuclear Information System (INIS)

    James, R.D.; Pointon, R.C.S.

    1985-01-01

    At the time of writing, radiotherapy is of only minor use in the management of adenocarcinoma of the gastrointestinal tract, for a number of reasons. First, an exploratory laparotomy is generally needed for diagnosis, and if possible the tumour is resected or by-passed. Second, radiotherapy planning in the upper abdomen is complicated by the proximity of small bowel, kidneys, and spinal cord. Third, it has been assumed that these tumours cause death largely as a result of distant metastases, so that local radiotherapy, even if effective, would contribute little to survival. The continued interest in radiotherapy for this group of tumours arises out of the poor survival rates following surgery, which have not changed for many years, and the morbidity associated with their resection. It was hoped that the addition of cytotoxic agents to radical surgery would improve survival rates in carcinoma of the stomach and intraperitoneal colon. Despite a large number of well-organised prospective trials, using a variety of cytotoxic drugs, there is so far no evidence that the addition of chemotherapy to radical surgery improves survival for either tumour site. The authors are therefore faced with a group of tumours which are not only common, but commonly fatal and many surgeons would accept that a new approach using modern radiotherapy techniques may well be justified. There is evidence that this movement is already taking place for carcinoma of the rectum, and the indications for radiotherapy in this condition will be dealt with below. Before considering these it is worth dwelling briefly on recent changes in surgical and radiological practices which, if they fulfil expectations, might allow radiotherapy to be used for carcinoma of the colon, stomach, and pancreas as it is now used for rectal cancer

  7. High precision spectroscopy of 32S, 33S and 34S sulfur dioxide:  Ultraviolet absorption cross sections and fractionation constants

    DEFF Research Database (Denmark)

    Danielache, Sebastian Oscar; Eskebjerg, Carsten; Johnson, Matthew Stanley

    2008-01-01

    spectra show rich vibrational structure, and the positions and widths of the peaks change with isotopic substitution in a complex fashion. The results imply that large wavelength-dependent and broadband isotopic fractionations are associated with the UV photolysis of SO2. Udgivelsesdato: 13 September 2008...

  8. Stem Cells in Repair of Gastrointestinal Epithelia

    NARCIS (Netherlands)

    Andersson-Rolf, Amanda; Zilbauer, Matthias; Koo, Bon-Kyoung; Clevers, Hans

    Among the endodermal tissues of adult mammals, the gastrointestinal (GI) epithelium exhibits the highest turnover rate. As the ingested food moves along the GI tract, gastric acid, digestive enzymes, and gut resident microbes aid digestion as well as nutrient and mineral absorption. Due to the harsh

  9. Zinc and gastrointestinal disease

    Institute of Scientific and Technical Information of China (English)

    Sonja; Skrovanek; Katherine; DiGuilio; Robert; Bailey; William; Huntington; Ryan; Urbas; Barani; Mayilvaganan; Giancarlo; Mercogliano; James; M; Mullin

    2014-01-01

    This review is a current summary of the role that both zinc deficiency and zinc supplementation can play in the etiology and therapy of a wide range of gastrointestinal diseases. The recent literature describing zinc action on gastrointestinal epithelial tight junctions and epithelial barrier function is described. Zinc enhancement of gastrointestinal epithelial barrier function may figure prominently in its potential therapeutic action in several gastrointestinal diseases.

  10. Tunable diode laser absorption spectroscopy-based tomography system for on-line monitoring of two-dimensional distributions of temperature and H{sub 2}O mole fraction

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lijun, E-mail: lijunxu@buaa.edu.cn; Liu, Chang; Jing, Wenyang; Cao, Zhang [School of Instrument Science and Opto-Electronic Engineering, Beihang University, Beijing 100191 (China); Ministry of Education’s Key Laboratory of Precision Opto-Mechatronics Technology, Beijing 100191 (China); Xue, Xin; Lin, Yuzhen [School of Energy and Power Engineering, Beihang University, Beijing 100191 (China)

    2016-01-15

    To monitor two-dimensional (2D) distributions of temperature and H{sub 2}O mole fraction, an on-line tomography system based on tunable diode laser absorption spectroscopy (TDLAS) was developed. To the best of the authors’ knowledge, this is the first report on a multi-view TDLAS-based system for simultaneous tomographic visualization of temperature and H{sub 2}O mole fraction in real time. The system consists of two distributed feedback (DFB) laser diodes, a tomographic sensor, electronic circuits, and a computer. The central frequencies of the two DFB laser diodes are at 7444.36 cm{sup −1} (1343.3 nm) and 7185.6 cm{sup −1} (1391.67 nm), respectively. The tomographic sensor is used to generate fan-beam illumination from five views and to produce 60 ray measurements. The electronic circuits not only provide stable temperature and precise current controlling signals for the laser diodes but also can accurately sample the transmitted laser intensities and extract integrated absorbances in real time. Finally, the integrated absorbances are transferred to the computer, in which the 2D distributions of temperature and H{sub 2}O mole fraction are reconstructed by using a modified Landweber algorithm. In the experiments, the TDLAS-based tomography system was validated by using asymmetric premixed flames with fixed and time-varying equivalent ratios, respectively. The results demonstrate that the system is able to reconstruct the profiles of the 2D distributions of temperature and H{sub 2}O mole fraction of the flame and effectively capture the dynamics of the combustion process, which exhibits good potential for flame monitoring and on-line combustion diagnosis.

  11. Radiation injuries of the gastrointestinal tract in Hodgkin's disease: the role of exploratory laparotomy and fractionation. A study of 19 cases observed in a series of 134 patients treated at the Institut Gustave Roussy from 1972 to 1982

    Energy Technology Data Exchange (ETDEWEB)

    Gallez-Marchal, D.; Fayolle, M.; Henry-Amar, M.; Le Bourgeois, J.P.; Rougier, P.; Cosset, J.M. (Institut Gustave Roussy, 94 - Villejuif (France))

    1984-01-01

    Out of 134 patients irradiated below the diaphragm to a dose of 40 Gy for Hodgkin's disease at the Institut Gustave-Roussy, 19 (14%) were subsequently found to present with radiation injuries of the gastrointestinal tract. Since five patients presented with two different injuries, 24 radiolesions were observed. Most of them (17 out of 24) were gastric or duodenal. Twelve (out of 24) were ulcers. Nine patients required surgery. A complete cure of the radiation injuries was obtained in 15 out of 19 patients. Sex, age, stage, histology or initial chemotherapy were not found to play a role in the occurrence of radiation damage. On the contrary, the role of a previous exploratory laparotomy appeared important; for the patients who underwent laparotomy and irradiation, the complication rate was 23%. For the patients treated by irradiation alone, the complication rate was 7% (p < 0.01). Fractionation was found to be another important parameter: for 52 patients treated using 3 weekly fractions of 3.3 Gy, the complication rate was 25% compared to 8% (p < 0.01) for 76 patients treated using 4 weekly fractions of 2.5 Gy. Combining these two factors, the authors found a 42% complication rate for the group of patients who underwent laparotomy and who were treated by means of 3 fractions of 3.3 Gy per week, whereas patients irradiated using 4 weekly fractions of 2.5 Gy, without any previous laparotomy, has only a 5% complication risk (p < 0.001).

  12. Diffuse Reflectance Spectroscopy of Hidden Objects, Part I: Interpretation of the Reflection-Absorption-Scattering Fractions in Near-Infrared (NIR) Spectra of Polyethylene Films.

    Science.gov (United States)

    Pomerantsev, Alexey L; Rodionova, Oxana Ye; Skvortsov, Alexej N

    2017-08-01

    Investigation of a sample covered by an interfering layer is required in many fields, e.g., for process control, biochemical analysis, and many other applications. This study is based on the analysis of spectra collected by near-infrared (NIR) diffuse reflectance spectroscopy. Each spectrum is a composition of a useful, target spectrum and a spectrum of an interfering layer. To recover the target spectrum, we suggest using a new phenomenological approach, which employs the multivariate curve resolution (MCR) method. In general terms, the problem is very complex. We start with a specific problem of analyzing a system, which consists of several layers of polyethylene (PE) film and underlayer samples with known spectral properties. To separate information originating from PE layers and the target, we modify the system versus both the number of the PE layers as well as the reflectance properties of the target sample. We consider that the interfering spectrum of the layer can be modeled using three components, which can be tentatively called transmission, absorption, and scattering contributions. The novelty of our approach is that we do not remove the reflectance and scattering effects from the spectra, but study them in detail aiming to use this information to recover the target spectrum.

  13. Influence of the Metal Volume Fraction on the permanent dent depth and energy absorption of GLARE plates subjected to low velocity impact

    Science.gov (United States)

    Bikakis, GSE; Savaidis, A.; Zalimidis, P.; Tsitos, S.

    2016-11-01

    Fiber-metal laminates are hybrid composite materials, consisting of alternating metal layers bonded to fiber-reinforced prepreg layers. GLARE (GLAss REinforced) belongs to this new family of materials. GLARE is the most successful fiber-metal laminate up to now and is currently being used for the construction of primary aerospace structures, such as the fuselage of the Airbus A380 air plane. Impact properties are very important in aerospace structures, since impact damage is caused by various sources, such as maintenance damage from dropped tools, collision between service cars or cargo and the structure, bird strikes and hail. The principal objective of this article is to evaluate the influence of the Metal Volume Fraction (MVF) on the low velocity impact response of GLARE fiber-metal laminates. Previously published differential equations of motion are employed for this purpose. The low velocity impact behavior of various circular GLARE plates is predicted and characteristic values of impact variables, which represent the impact phenomenon, are evaluated versus the corresponding MVF of the examined GLARE material grades. The considered GLARE plates are subjected to low velocity impact under identical impact conditions. A strong effect of the MVF on the maximum impact load and a significant effect on the maximum plate deflection of GLARE plates has been found.

  14. Usage of X-ray absorption spectroscopy and extractive fractionation in studies of the Cu (II and Zn (II ions in soils

    Directory of Open Access Journals (Sweden)

    Dina Nevidomskaya

    2014-12-01

    Full Text Available XANES spectroscopy is an effective method for the study of bonds between metals and soil components. The study of structural organization in different soil samples and soil phases saturated with Cu2+ and Zn2+ ions by using XANES allowed determining the mechanism of their interaction with soil phases and all the chemical bindings taken place in the course of this process. Changes in the structure of the metal ion, in particular breakdown of the symmetry of electron orbits of atoms, take place due to interaction with soil components. Application of this method demonstrated that the state of copper and zinc introduced in chernozem as oxides did not change after one year of incubation. Copper is absorbed after being introduced as soluble salts, and copper ions are incorporated in the octahedral and tetrahedral sites of minerals and bonded with humic materials at the expense of covalent bond and the formation of coordination humate copper complexes. Zinc included into octahedric structures of layered minerals and hydro(oxides can be inner-and outer-sphere adsorbed. It is shown that the action of the metal bound to soil components becomes weakened in case of increasing the Cu and Zn load (from 2000 to 10000 mg/kg especially applied in the form of soluble salts. Extractive fractionation of metal compounds in chernozem samples, artificially contaminated with copper and zinc salts serves as evidence of absorbing the applied Cu2+ ions by the soil organic matter and Zn2+ ions – by silicates, carbonates, and Fe-Mn oxides.

  15. Effects of radiation upon gastrointestinal motility

    Institute of Scientific and Technical Information of China (English)

    Mary F Otterson

    2007-01-01

    Whether due to therapeutic or belligerent exposure, the gastrointestinal effects of irradiation produce symptoms dreaded by a majority of the population. Nausea, vomiting, diarrhea and abdominal cramping are hallmarks of the prodromal phase of radiation sickness, occurring hours to days following radiation exposure. The prodromal phase is distinct from acute radiation sickness in that the absorptive, secretory and anatomic changes associated with radiation damage are not easily identifiable. It is during this phase of radiation sickness that gastrointestinal motility significantly changes. In addition, there is evidence that motor activity of the gut contributes to some of the acute and chronic effects of radiation.

  16. Nonvariceal upper gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Burke, Stephen J.; Weldon, Derik; Sun, Shiliang; Golzarian, Jafar

    2007-01-01

    Nonvariceal upper gastrointestinal bleeding (NUGB) remains a major medical problem even after advances in medical therapy with gastric acid suppression and cyclooxygenase (COX-2) inhibitors. Although the incidence of upper gastrointestinal bleeding presenting to the emergency room has slightly decreased, similar decreases in overall mortality and rebleeding rate have not been experienced over the last few decades. Many causes of upper gastrointestinal bleeding have been identified and will be reviewed. Endoscopic, radiographic and angiographic modalities continue to form the basis of the diagnosis of upper gastrointestinal bleeding with new research in the field of CT angiography to diagnose gastrointestinal bleeding. Endoscopic and angiographic treatment modalities will be highlighted, emphasizing a multi-modality treatment plan for upper gastrointestinal bleeding. (orig.)

  17. Nonvariceal upper gastrointestinal bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Burke, Stephen J.; Weldon, Derik; Sun, Shiliang [University of Iowa, Department of Radiology, Iowa, IA (United States); Golzarian, Jafar [University of Iowa, Department of Radiology, Iowa, IA (United States); University of Iowa, Department of Radiology, Carver College of Medicine, Iowa, IA (United States)

    2007-07-15

    Nonvariceal upper gastrointestinal bleeding (NUGB) remains a major medical problem even after advances in medical therapy with gastric acid suppression and cyclooxygenase (COX-2) inhibitors. Although the incidence of upper gastrointestinal bleeding presenting to the emergency room has slightly decreased, similar decreases in overall mortality and rebleeding rate have not been experienced over the last few decades. Many causes of upper gastrointestinal bleeding have been identified and will be reviewed. Endoscopic, radiographic and angiographic modalities continue to form the basis of the diagnosis of upper gastrointestinal bleeding with new research in the field of CT angiography to diagnose gastrointestinal bleeding. Endoscopic and angiographic treatment modalities will be highlighted, emphasizing a multi-modality treatment plan for upper gastrointestinal bleeding. (orig.)

  18. Effect of oils on drug absorption

    OpenAIRE

    Palin, K.J.

    1981-01-01

    Oil and emulsion vehicles have been shown to alter the oral absorption of many drugs. This may be due to enhanced lymph flow and/or altered gastro-intestinal motility in the presence of the oils. The oral absorption of a model compound (DOT) in the presence of three chemically different oils, arachis oil, Miglyol 812 and liquid paraffin was investigated in rats, the influence of lymphatic absorption and gastro-intestinal motility being determined. The findings were applied to the for.mulation...

  19. Gastrointestinal nuclear imaging

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    This book contains paper grouped under the headings of: salivary scintigraphy, abscess detection with radionuclides; pediatric gastroenterology; liver spleen, and miscellaneous GI studies: gastrointestinal

  20. Bone marrow stromal cell transplantation mitigates radiation-induced gastrointestinal syndrome in mice.

    Directory of Open Access Journals (Sweden)

    Subhrajit Saha

    Full Text Available Nuclear accidents and terrorism presents a serious threat for mass casualty. While bone-marrow transplantation might mitigate hematopoietic syndrome, currently there are no approved medical countermeasures to alleviate radiation-induced gastrointestinal syndrome (RIGS, resulting from direct cytocidal effects on intestinal stem cells (ISC and crypt stromal cells. We examined whether bone marrow-derived adherent stromal cell transplantation (BMSCT could restitute irradiated intestinal stem cells niche and mitigate radiation-induced gastrointestinal syndrome.Autologous bone marrow was cultured in mesenchymal basal medium and adherent cells were harvested for transplantation to C57Bl6 mice, 24 and 72 hours after lethal whole body irradiation (10.4 Gy or abdominal irradiation (16-20 Gy in a single fraction. Mesenchymal, endothelial and myeloid population were characterized by flow cytometry. Intestinal crypt regeneration and absorptive function was assessed by histopathology and xylose absorption assay, respectively. In contrast to 100% mortality in irradiated controls, BMSCT mitigated RIGS and rescued mice from radiation lethality after 18 Gy of abdominal irradiation or 10.4 Gy whole body irradiation with 100% survival (p<0.0007 and p<0.0009 respectively beyond 25 days. Transplantation of enriched myeloid and non-myeloid fractions failed to improve survival. BMASCT induced ISC regeneration, restitution of the ISC niche and xylose absorption. Serum levels of intestinal radioprotective factors, such as, R-Spondin1, KGF, PDGF and FGF2, and anti-inflammatory cytokines were elevated, while inflammatory cytokines were down regulated.Mitigation of lethal intestinal injury, following high doses of irradiation, can be achieved by intravenous transplantation of marrow-derived stromal cells, including mesenchymal, endothelial and macrophage cell population. BMASCT increases blood levels of intestinal growth factors and induces regeneration of the irradiated

  1. Gastrointestinal polyposis in Cowden disease

    International Nuclear Information System (INIS)

    Kullnig, P.; Steiner, H.; Porsch, G.; Smolle, J.

    1987-01-01

    A case of Cowden disease (multiple hamartoma syndrome) with marked gastrointestinal polyposis is presented. The differential diagnosis of gastrointestinal polyposis syndromes is discussed. (orig.) [de

  2. Angiography and the gastrointestinal bleeder

    International Nuclear Information System (INIS)

    Baum, S.

    1982-01-01

    The role of angiography in the diagnosis and treatment of gastrointestinal hemorrhage is discussed. Three categories of gastrointestinal bleeding are considered: upper gastrointestinal bleeding due to gastroesophageal varices, upper gastrointestinal bleeding of arterial or capillary origin, and lower gastrointestinal bleeding. The advantages and disadvantages of angiography are compared with those of radionuclide scanning and endoscopy or colonoscopy. It is anticipated that, as radionuclide scans are more widely employed, angiography will eventually be performed only in those patients with positive scans

  3. RBE of some Sodium, Water and Bioelectric Parameters of Gastro-Intestinal Absorption; L'EBR pour le Transport du Sodium et de l'Eau et pour Certains Parametre Bioelectriques dans l'Absorption Gastro-Intestinale; Obeh v otnoshenii nekotorykh natrievykh, vodnykh i bioehlektricheskikh parametrov vsasyvaniya v zheludochno-kishechnom trakte; La EBR Para el Transporte del Sodio y del Agua y Para Ciertos Parametros Bioelectricos en la Absorcion Gastrointestinal

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, B. E.; Davis, A. K.; Cummins, J. T.; Alpen, E. L. [US Naval Radiological Defense Laboratory, San Francisco, CA (United States)

    1964-05-15

    Bioelectric and unidirectional flux measurements were made by methods previously reported. Rats and dogs were exposed to fast neutron and to 250 kVp X-irradiation (rats) or to 1000 kVp X-irradiation (dogs). Animals were exposed bilaterally to the whole body and depth dosimetry evaluated in each case. In the rat, seven days after irradiating, bioelectric activity is markedly reduced from normal in stomach but not at the lower gastrointestinal level. An RBE value of 2-3 can be established for delayed reduction in gastric bioelectric activity, and this effect is readily demonstrated at neutron doses of 160 rad (1st collision). In the dog, three days after irradiating, the unidirectional transfer rates from plasma-to-lumen are decreased for sodium and for water. This occurs after X-irradiation at 1200 r (air dose) and after neutron irradiation at either 300 rad or 600 rad (1st collision). However, at 600 r X-irradiation doses (air) these transfer rates do not show a decrease, and tend in the opposite direction. An RBE value lying between 2 and 6 can be inferred for the delayed reduction in plasma-to-lumen transfers. The electrogenic mechanism in rat stomach as here studied shows sodium-ion specificity, unlike that in frog stomach. Potentials as measured in vitro agree with those measured in vivo, and they are unaffected except by metabolic poisoning or sodium replacement. Contrasting with bioelectric parameters flux determinations are a more specific measurement; however marked biological variability limits their utility. Plasma- to-lumen unidirectional fluxes show a consistent pattern of change with respect to irradiation, indicative of decreased permeability at the higher irradiation doses. (author) [French] Les auteurs ont utilise des methodes deja decrites pour determiner l'activite bioelectrique et mesurer des cornants unidirectionnels. Des rats et des chiens ont ete exposes a des neutrons rapides et a des rayons X de 250 kV-crete et de 1000 k

  4. Calcium absorption

    International Nuclear Information System (INIS)

    Carlmark, B.; Reizenstein, P.; Dudley, R.A.

    1976-01-01

    The methods most commonly used to measure the absorption and retention of orally administered calcium are reviewed. Nearly all make use of calcium radioisotopes. The magnitude of calcium absorption and retention depends upon the chemical form and amount of calcium administered, and the clinical and nutritional status of the subject; these influences are briefly surveyed. (author)

  5. Absorption studies

    International Nuclear Information System (INIS)

    Ganatra, R.D.

    1992-01-01

    Absorption studies were once quite popular but hardly anyone does them these days. It is easier to estimate the blood level of the nutrient directly by radioimmunoassay (RIA). However, the information obtained by estimating the blood levels of the nutrients is not the same that can be obtained from the absorption studies. Absorption studies are primarily done to find out whether some of the essential nutrients are absorbed from the gut or not and if they are absorbed, to determine how much is being absorbed. In the advanced countries, these tests were mostly done to detect pernicious anaemia where vitamin B 12 is not absorbed because of the lack of the intrinsic factor in the stomach. In the tropical countries, ''malabsorption syndrome'' is quire common. In this condition, several nutrients like fat, folic acid and vitamin B 12 are not absorbed. It is possible to study absorption of these nutrients by radioisotopic absorption studies

  6. Detoxification of carbaryl by anaerobic gastrointestinal organisms

    International Nuclear Information System (INIS)

    Laszewski, S.J.; Harkin, J.M.

    1990-01-01

    Bacteria originating from the human gastrointestinal tract (GIT) were tested in vitro for their ability to hydrolyze carbaryl, the most widely used carbamate insecticide. Carbaryl hydrolysis prevents acetylcholinesterase inhibition. Degradation of [1- 14 C]naphthyl N-methylcarbamate was assessed through the use of carbon-and nitrogen-free enrichment cultures as well as a cometabolic enrichment culture. The carbon-free enrichment culture showed the greatest ability to hydrolyze carbaryl. Two facultative anaerobes, identified as DF-3 and Citrobacter freundii were isolated. Cell-free extracts from these bacteria were able to hydrolyze p-nitrophenyl acetate, 1-naphthyl acetate and carbaryl. This investigation suggests carbaryl degradation could occur prior to gastrointestinal absorption. Human GIT organisms are also widespread in anaerobic environments. Microbial hydrolysis of a xenobiotic can be an important reaction in the anaerobic environments of man or nature

  7. Measurement of void fractions by nuclear techniques

    International Nuclear Information System (INIS)

    Hernandez G, A.; Vazquez G, J.; Diaz H, C.; Salinas R, G.A.

    1997-01-01

    In this work it is done a general analysis of those techniques used to determine void fractions and it is chosen a nuclear technique to be used in the heat transfer circuit of the Physics Department of the Basic Sciences Management. The used methods for the determination of void fractions are: radioactive absorption, acoustic techniques, average velocity measurement, electromagnetic flow measurement, optical methods, oscillating absorption, nuclear magnetic resonance, relation between pressure and flow oscillation, infrared absorption methods, sound neutron analysis. For the case of this work it will be treated about the radioactive absorption method which is based in the gamma rays absorption. (Author)

  8. Folate absorption

    International Nuclear Information System (INIS)

    Baker, S.J.

    1976-01-01

    Folate is the generic term given to numerous compounds of pteroic acid with glutamic acid. Knowledge of absorption is limited because of the complexities introduced by the variety of compounds and because of the inadequacy of investigational methods. Two assay methods are in use, namely microbiological and radioactive. Techniques used to study absorption include measurement of urinary excretion, serum concentration, faecal excretion, intestinal perfusion, and haematological response. It is probably necessary to test absorption of both pteroylmonoglutamic acid and one or more polyglutamates, and such tests would be facilitated by availability of synthesized compounds labelled with radioactive tracers at specifically selected sites. (author)

  9. FRACTIONAL BANKING

    OpenAIRE

    Maria Klimikova

    2010-01-01

    Understanding the reasons of the present financial problems lies In understanding the substance of fractional reserve banking. The substance of fractional banking is in lending more money than the bankers have. Banking of partial reserves is an alternative form which links deposit banking and credit banking. Fractional banking is causing many unfavorable economic impacts in the worldwide system, specifically an inflation.

  10. Absorption of orally administered 65Zn by normal human subjects

    International Nuclear Information System (INIS)

    Aamodt, R.L.; Rumble, W.F.; Johnston, G.S.; Markley, E.J.; Henkin, R.I.

    1981-01-01

    Despite studies by several investigators of human gastrointestinal 65Zn absorption, implications of these data for evaluation of functional zinc status are unclear because limited numbers of normal subjects have been studied. To evaluated zinc absorption in normal humans, 75 subjects (31 women, 44 men, ages 18 to 84 yr) were given 10 micro Ci carrier-free 65Zn orally after an overnight fast. Absorption calculated from total body retention measured 7, 14, and 21 days after administration of tracer was 65 +/- 11% (mean +/- 1 SD), range from 40 to 86%. Comparison of these results with those for patients with a variety of diseases indicate that patients exhibit a wider range of absorption and, in four of six studies patients exhibit decreased mean zinc absorption. These results of gastrointestinal zinc absorption in a large number of normal humans offer a basis for a clearer comparison with data from patients who exhibit abnormalities of zinc absorption

  11. Management of gastrointestinal hemorrhage.

    OpenAIRE

    Hilsden, R. J.; Shaffer, E. A.

    1995-01-01

    Acute gastrointestinal hemorrhage is a common problem that requires prompt recognition and management to prevent serious morbidity and mortality. Management goals are stabilization of the patient with vigorous fluid resuscitation followed by investigation and definitive treatment of the bleeding source. Endoscopy is often the initial diagnostic test and allows therapeutic measures to be performed at the same time.

  12. Fractional thermoelasticity

    CERN Document Server

    Povstenko, Yuriy

    2015-01-01

    This book is devoted to fractional thermoelasticity, i.e. thermoelasticity based on the heat conduction equation with differential operators of fractional order. Readers will discover how time-fractional differential operators describe memory effects and space-fractional differential operators deal with the long-range interaction. Fractional calculus, generalized Fourier law, axisymmetric and central symmetric problems and many relevant equations are featured in the book. The latest developments in the field are included and the reader is brought up to date with current research.  The book contains a large number of figures, to show the characteristic features of temperature and stress distributions and to represent the whole spectrum of order of fractional operators.  This work presents a picture of the state-of-the-art of fractional thermoelasticity and is suitable for specialists in applied mathematics, physics, geophysics, elasticity, thermoelasticity and engineering sciences. Corresponding sections of ...

  13. Probiotics: defenders of gastrointestinal habitats

    Directory of Open Access Journals (Sweden)

    Desh D. Singh

    2012-11-01

    Full Text Available Intestinal microbiota play an important role in maintaining normal gastrointestinal (GI function and ensuring that changes in the composition of the intestinal microbiota can promote GI function. The digestive tract is full of bacteria and many of these, including probiotics, are necessary for optimal digestive function. During bacterial gastroenteritis, harmful bacteria invade the digestive tract causing unpleasant symptoms and upsetting the balance between good and bad bacteria. Supplemental probiotics can help restore this balance. Studies have demonstrated that probiotics can often help reduce the severity of symptoms such as diarrhea and may help accelerate recovery. Probiotics are therapeutic preparations of live microorganisms administered in sufficient dosage to be beneficial to health. The therapeutic effects of these microorganisms appear to be strain specific. Primal Defense®, a unique, probiotic, bacterial compound, contains probiotics that support gut flora balance, promote consistent bowel function, control stomach acid levels to quickly eliminate burning sensation in the stomach and maintain immune system response. The probiotics in Primal Defense® maximize the benefits of a healthy diet by supporting normal absorption and assimilation of nutrients in the gut. Nearly 75% of our immune defenses are located in the digestive tract, so maintaining a favorable bacterial balance in the intestines (ideally 80% good or neutral bacteria to 20% bad or harmful bacteria is crucial to achieving and maintaining optimum health.

  14. GASTROINTESTINAL STROMAL TUMOR (GIST

    Directory of Open Access Journals (Sweden)

    Luigi eTornillo

    2014-11-01

    Full Text Available Gastrointestinal stromal tumors are the most frequent mesenchymal tumors of the gastrointestinal tract. The discovery that these tumors, formerly thought of smooth muscle origin, are indeed better characterized by specific activating mutation in genes coding for the receptor tyrosine kinases CKIT and PDGFRA and that these mutations are strongly predictive for the response to targeted therapy with receptor tyrosine kinase inhibitors has made GISTs the typical example of the integration of basic molecular knowledge in the daily clinical activity. The information on the mutational status of these tumors is essential to predict (and subsequently to plan the therapy. As resistant cases are frequently wild-type, other possible oncogenic events, defining other entities, have been discovered (e.g. succinil dehydrogenase mutation/dysregulation, insuline growth factor expression, mutations in the RAS-RAF-MAPK pathway. The classification of disease must nowadays rely on the integration of the clinico-morphological characteristics with the molecular data.

  15. Radiology illustrated. Gastrointestinal tract

    International Nuclear Information System (INIS)

    Choi, Byung Ihn

    2015-01-01

    Radiology Illustrated: Gastrointestinal Tract is the second of two volumes designed to provide clear and practical guidance on the diagnostic imaging of abdominal diseases. The book presents approximately 300 cases with 1500 carefully selected and categorized illustrations of gastrointestinal tract diseases, along with key text messages and tables that will help the reader easily to recall the relevant images as an aid to differential diagnosis., Essential points are summarized at the end of each text message to facilitate rapid review and learning. Additionally, brief descriptions of each clinical problem are provided, followed by case studies of both common and uncommon pathologies that illustrate the roles of the different imaging modalities, including ultrasound, radiography, computed tomography, and magnetic resonance imaging.

  16. Radiology illustrated. Gastrointestinal tract

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Byung Ihn (ed.) [Seoul National University Hospital (Korea, Republic of). Dept. of Radiology

    2015-02-01

    Radiology Illustrated: Gastrointestinal Tract is the second of two volumes designed to provide clear and practical guidance on the diagnostic imaging of abdominal diseases. The book presents approximately 300 cases with 1500 carefully selected and categorized illustrations of gastrointestinal tract diseases, along with key text messages and tables that will help the reader easily to recall the relevant images as an aid to differential diagnosis., Essential points are summarized at the end of each text message to facilitate rapid review and learning. Additionally, brief descriptions of each clinical problem are provided, followed by case studies of both common and uncommon pathologies that illustrate the roles of the different imaging modalities, including ultrasound, radiography, computed tomography, and magnetic resonance imaging.

  17. Gastrointestinal Complications of Obesity

    Science.gov (United States)

    Camilleri, Michael; Malhi, Harmeet; Acosta, Andres

    2017-01-01

    Obesity usually is associated with morbidity related to diabetes mellitus and cardiovascular diseases. However, there are many gastrointestinal and hepatic diseases for which obesity is the direct cause (eg, nonalcoholic fatty liver disease) or is a significant risk factor, such as reflux esophagitis and gallstones. When obesity is a risk factor, it may interact with other mechanisms and result in earlier presentation or complicated diseases. There are increased odds ratios or relative risks of several gastrointestinal complications of obesity: gastroesophageal reflux disease, erosive esophagitis, Barrett’s esophagus, esophageal adenocarcinoma, erosive gastritis, gastric cancer, diarrhea, colonic diverticular disease, polyps, cancer, liver disease including nonalcoholic fatty liver disease, cirrhosis, hepatocellular carcinoma, gallstones, acute pancreatitis, and pancreatic cancer. Gastroenterologists are uniquely poised to participate in the multidisciplinary management of obesity as physicians caring for people with obesity-related diseases, in addition to their expertise in nutrition and endoscopic interventions. PMID:28192107

  18. Gastrointestinal food allergies.

    Science.gov (United States)

    Heine, Ralf G

    2015-01-01

    Gastrointestinal food allergies present during early childhood with a diverse range of symptoms. Cow's milk, soy and wheat are the three most common gastrointestinal food allergens. Several clinical syndromes have been described, including food protein-induced enteropathy, proctocolitis and enterocolitis. In contrast with immediate, IgE-mediated food allergies, the onset of gastrointestinal symptoms is delayed for at least 1-2 hours after ingestion in non-IgE-mediated allergic disorders. The pathophysiology of these non-IgE-mediated allergic disorders is poorly understood, and useful in vitro markers are lacking. The results of the skin prick test or measurement of the food-specific serum IgE level is generally negative, although low-positive results may occur. Diagnosis therefore relies on the recognition of a particular clinical phenotype as well as the demonstration of clear clinical improvement after food allergen elimination and the re-emergence of symptoms upon challenge. There is a significant clinical overlap between non-IgE-mediated food allergy and several common paediatric gastroenterological conditions, which may lead to diagnostic confusion. The treatment of gastrointestinal food allergies requires the strict elimination of offending food allergens until tolerance has developed. In breast-fed infants, a maternal elimination diet is often sufficient to control symptoms. In formula-fed infants, treatment usually involves the use an extensively hydrolysed or amino acid-based formula. Apart from the use of hypoallergenic formulae, the solid diets of these children also need to be kept free of specific food allergens, as clinically indicated. The nutritional progress of infants and young children should be carefully monitored, and they should undergo ongoing, regular food protein elimination reassessments by cautious food challenges to monitor for possible tolerance development. © 2015 S. Karger AG, Basel.

  19. Upper gastrointestinal bleeding.

    Science.gov (United States)

    Feinman, Marcie; Haut, Elliott R

    2014-02-01

    Upper gastrointestinal (GI) bleeding remains a commonly encountered diagnosis for acute care surgeons. Initial stabilization and resuscitation of patients is imperative. Stable patients can have initiation of medical therapy and localization of the bleeding, whereas persistently unstable patients require emergent endoscopic or operative intervention. Minimally invasive techniques have surpassed surgery as the treatment of choice for most upper GI bleeding. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Orexins and gastrointestinal functions.

    Science.gov (United States)

    Baccari, M C

    2010-03-01

    Orexin A (OXA) and orexin B (OXB) are recently discovered neuropeptides that appear to play a role in various distinct functions such as arousal and the sleep-wake cycle as well as on appetite and regulation of feeding and energy homeostasis. Orexins were first described as neuropeptides expressed by a specific population of neurons in the lateral hypothalamic area, a region classically implicated in feeding behaviour. Orexin neurons project to numerous brain regions, where orexin receptors have been shown to be widely distributed: both OXA and OXB act through two subtypes of receptors (OX1R and OX2R) that belong to the G protein-coupled superfamily of receptors. Growing evidence indicates that orexins act in the central nervous system also to regulate gastrointestinal functions: animal studies have indeed demonstrated that centrally-injected orexins or endogenously released orexins in the brain stimulates gastric secretion and influence gastrointestinal motility. The subsequent identification of orexins and their receptors in the enteric nervous system (including the myenteric and the submucosal plexuses) as well as in mucosa and smooth muscles has suggested that these neuropeptides may also play a local action. In this view, emerging studies indicate that orexins also exert region-specific contractile or relaxant effects on isolated gut preparations. The aim of the proposed review is to summarize both centrally- and peripherally-mediated actions of orexins on gastrointestinal functions and to discuss the related physiological role on the basis of the most recent findings.

  1. Narrative absorption

    DEFF Research Database (Denmark)

    Narrative Absorption brings together research from the social sciences and Humanities to solve a number of mysteries: Most of us will have had those moments, of being totally absorbed in a book, a movie, or computer game. Typically we do not have any idea about how we ended up in such a state. No...

  2. Fractional charges

    International Nuclear Information System (INIS)

    Saminadayar, L.

    2001-01-01

    20 years ago fractional charges were imagined to explain values of conductivity in some materials. Recent experiments have proved the existence of charges whose value is the third of the electron charge. This article presents the experimental facts that have led theorists to predict the existence of fractional charges from the motion of quasi-particles in a linear chain of poly-acetylene to the quantum Hall effect. According to the latest theories, fractional charges are neither bosons nor fermions but anyons, they are submitted to an exclusive principle that is less stringent than that for fermions. (A.C.)

  3. Absorption of controlled-release iron

    International Nuclear Information System (INIS)

    Cook, J.D.; Lipschitz, D.A.; Skikne, B.S.

    1982-01-01

    A multiple-dose double radioiron technic was used to compare absorption of iron administered as a controlled release (CR) capsule and as an elixir; both formulations contained 50 mg elemental iron as ferrous sulfate. When taken by normal subjects in the fasting state, mean absorption from the elixir and CR capsule averaged 4.92% and 4.38%, which gave a CR capsule:elixir ratio of 0.89. This difference was not significant, but when taken with meals that inhibit absorption of dietary iron by different degrees, absorption of the CR formulation was superior. CR capsule:elixir absorption ratios averaged 1.70 from a meal that is mildly inhibitory and 3.13 from a meal that causes more marked inhibition. It is concluded that CR iron formulations may offer a therapeutic advantage to patients who take oral iron with meals to avoid gastrointestinal side effects

  4. Absorptive products

    International Nuclear Information System (INIS)

    Assarsson, P.G.; King, P.A.

    1976-01-01

    Applications for hydrophile gels produced by the radiation induced cross-linking in aqueous solution of polyethylene oxide and starch, as described in Norwegian patent 133501 (INIS RN 281494), such as sanitary napkins (diapers) and sanitary towels, are discussed. The process itself is also discussed and results, expressed as the percentage of insoluble gel and its absorptive capacity for saline solution as functions of the ratio of polyethylene oxide to starch and the radiation dose, are presented. (JIW)

  5. Fractional fermions

    International Nuclear Information System (INIS)

    Jackiw, R.; Massachusetts Inst. of Tech., Cambridge; Massachusetts Inst. of Tech., Cambridge

    1984-01-01

    The theory of fermion fractionization due to topologically generated fermion ground states is presented. Applications to one-dimensional conductors, to the MIT bag, and to the Hall effect are reviewed. (author)

  6. Embolization for gastrointestinal hemorrhages

    International Nuclear Information System (INIS)

    Kraemer, S.C.; Goerich, J.; Rilinger, N.; Aschoff, A.J.; Vogel, J.; Brambs, H.J.; Siech, M.

    2000-01-01

    Retrospective evaluation of interventional embolization therapy in the treatment of gastrointestinal hemorrhage over a long-term observation period from 1989 to 1997. Included in the study were 35 patients (age range 18-89 years) with gastrointestinal bleeding (GI) referred for radiological intervention either primarily or following unsuccessful endoscopy or surgery. Sources of GI bleeding included gastric and duodenal ulcers (n = 7), diverticula (n = 3), erosion of the intestinal wall secondary to malignancy (n = 6), vascular malformations (n = 4), and hemorrhoids (n = 2), as well as from postoperative (n = 6), posttraumatic (n = 2), postinflammatory (n = 4) or unknown (n = 1) causes. Ethibloc (12 cases) or metal coils (14 cases) were predominantly used as embolisates. In addition, combinations of tissue adhesive and gelfoam particles and of coils and Ethibloc were used (six cases). Finally, polyvinyl alcohol particles, a coated stent, and an arterial wire dissection were utilized in one case each. Bleeding was stopped completely in 29 of 35 cases (83 %). In one case (3 %) the source of bleeding was recognized but the corresponding vessel could not be catheterized. In five other cases (14 %) there was partial success with reduced, though still persistent, bleeding. The rate of complications was 14 %, including four instances of intestinal ischemia with fatal outcome in the first years, and, later, one partial infarction of the spleen without serious consequences. Gastrointestinal hemorrhage can be controlled in a high percentage of patients, including the seriously ill and those who had previously undergone surgery, with the use of minimally invasive interventional techniques. The availability of minicoils instead of fluid embolization agents has reduced the risk of serious complications. (orig.)

  7. Embolization for gastrointestinal hemorrhages

    Energy Technology Data Exchange (ETDEWEB)

    Kraemer, S.C.; Goerich, J.; Rilinger, N.; Aschoff, A.J.; Vogel, J.; Brambs, H.J. [Dept. of Diagnostic Radiology, University of Ulm (Germany); Siech, M. [Dept. of Abdominal Surgery, University of Ulm (Germany)

    2000-05-01

    Retrospective evaluation of interventional embolization therapy in the treatment of gastrointestinal hemorrhage over a long-term observation period from 1989 to 1997. Included in the study were 35 patients (age range 18-89 years) with gastrointestinal bleeding (GI) referred for radiological intervention either primarily or following unsuccessful endoscopy or surgery. Sources of GI bleeding included gastric and duodenal ulcers (n = 7), diverticula (n = 3), erosion of the intestinal wall secondary to malignancy (n = 6), vascular malformations (n = 4), and hemorrhoids (n = 2), as well as from postoperative (n = 6), posttraumatic (n = 2), postinflammatory (n = 4) or unknown (n = 1) causes. Ethibloc (12 cases) or metal coils (14 cases) were predominantly used as embolisates. In addition, combinations of tissue adhesive and gelfoam particles and of coils and Ethibloc were used (six cases). Finally, polyvinyl alcohol particles, a coated stent, and an arterial wire dissection were utilized in one case each. Bleeding was stopped completely in 29 of 35 cases (83 %). In one case (3 %) the source of bleeding was recognized but the corresponding vessel could not be catheterized. In five other cases (14 %) there was partial success with reduced, though still persistent, bleeding. The rate of complications was 14 %, including four instances of intestinal ischemia with fatal outcome in the first years, and, later, one partial infarction of the spleen without serious consequences. Gastrointestinal hemorrhage can be controlled in a high percentage of patients, including the seriously ill and those who had previously undergone surgery, with the use of minimally invasive interventional techniques. The availability of minicoils instead of fluid embolization agents has reduced the risk of serious complications. (orig.)

  8. in upper gastrointestinal endoscopy

    Directory of Open Access Journals (Sweden)

    Sinan Uzman

    2016-07-01

    Full Text Available Introduction : There is increasing interest in sedation for upper gastrointestinal endoscopy (UGE. Prospective randomized studies comparing sedation properties and complications of propofol and midazolam/meperidine in upper gastrointestinal endoscopy (UGE are few. Aim: To compare propofol and midazolam/meperidine sedation for UGE in terms of cardiopulmonary side effects, patient and endoscopist satisfaction and procedure-related times. Material and methods: This was a prospective, randomized, double-blind study of propofol versus midazolam and meperidine in 100 patients scheduled for diagnostic upper gastrointestinal endoscopy. The patients were divided into propofol and midazolam/meperidine groups. Randomization was generated by a computer. Cardiopulmonary side effects (hypotension, bradycardia, hypoxemia, procedure-related times (endoscopy time, awake time, time to hospital discharge, and patient and endoscopist satisfaction were compared between groups. Results: There was no significant difference between the groups with respect to the cost, endoscopy time, or demographic and clinical characteristics of the patients. Awake time and time to hospital discharge were significantly shorter in the propofol group (6.58 ±4.72 vs. 9.32 ±4.26 min, p = 0.030 and 27.60 ±7.88 vs. 32.00 ±10.54 min, p = 0.019. Hypotension incidence was significantly higher in the propofol group (12% vs. 0%, p = 0.027. The patient and endoscopist satisfaction was better with propofol. Conclusions : Propofol may be preferred to midazolam/meperidine sedation, with a shorter awake and hospital discharge time and better patient and endoscopist satisfaction. However, hypotension risk should be considered with propofol, and careful evaluation is needed, particularly in cardiopulmonary disorders.

  9. Gastrointestinal Headache; a Narrative Review

    OpenAIRE

    Majid T Noghani; Hossein Rezaeizadeh; Sayed Mohammad Baqer Fazljoo; Mahmoud Yousefifard; Mansoor Keshavarz

    2016-01-01

    There are studies reporting primary headaches to be associated with gastrointestinal disorders, and some report resolution of headache following the treatment of the associated gastrointestinal disorder. Headache disorders are classified by The International Headache Society as primary or secondary; however, among the secondary headaches, those attributed to gastrointestinal disorders are not appreciated. Therefore, we aimed to review the literature to provide evidence for headaches, which or...

  10. Gastrointestinal and hepatobiliary radiology

    International Nuclear Information System (INIS)

    Graham, R.N.J.; Perriss, R.W.; Scarsbrook, A.F.

    2006-01-01

    This is the fifth in the series of short reviews of internet-based radiological learning resources and will focus on gastrointestinal (GI) and hepatobiliary radiology. Below are details of a few of the higher quality resources currently available. Most of the sites cater for medical students and trainee or non-specialist radiologists, but may be also be of interest to specialists, especially for use in teaching. Hyperlinks are available in the electronic version of this article and were all active at the time of going to press (May 2006)

  11. Gastrointestinal stromal tumors

    International Nuclear Information System (INIS)

    Sufliarsky, J.

    2011-01-01

    Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the digestive tract. Better understanding of the molecular characteristics of GISTs led to the clinical development of imatinib for treating patients with this disease. New immuno markers and mechanisms of primary and secondary resistance were discovered. Adjuvant imatinib in intermediate or high risk GIST has improved the recurrence-free survival. Sunitinib in patients with intolerance or progression on imatinib demonstrated significant improvements in progression-free and overall survival versus placebo. Second-generation tyrosine kinase inhibitors, such as sorafenib, dasatinib, and nilotinib, have shown activity in patients with imatinib- and sunitinib-resistant GIST. (author)

  12. Gastrointestinal Manifestations of Cystic Fibrosis

    Science.gov (United States)

    2016-01-01

    Cystic fibrosis has historically been considered a pulmonary disease, but with the increasing life expectancy of these patients, gastrointestinal manifestations are becoming more important. Furthermore, nutritional status is closely linked to pulmonary function and, thus, overall mortality. This article discusses gastrointestinal manifestations (which involve nutritional, pancreatic, hepatobiliary, and, in particular, gastrointestinal tract issues) of cystic fibrosis as well as management of the disease. In addition, the article discusses studies that have been critical to our understanding of gastrointestinal manifestations of cystic fibrosis. PMID:27330503

  13. Gastrointestinal Eosinofilic Disorders

    International Nuclear Information System (INIS)

    Rodriguez Maria, Roberto; Bohorquez, Maria Amalia; Gonzalez, Irene; Torregroza, Gustavo

    2007-01-01

    The gastrointestinal eosinofilic disorders are little frequent diseases, of etiopatogenia little clear, that are characterized by the presence of an infiltrated eosinofilo that can affect the different layers of the wall of the alimentary canal in absence of known causes of eosinofilia. The clinical manifestations are variable and the symptoms are conditioned by the degree of eosinofilia of the wall, the number of layers affected and the segment of the gastrointestinal tract implied. The presentations symptoms vary from diarrhea, vomits, abdominal pain and loss of weigh until the acute intestinal obstruction. They are characterized to present peripherical eosinofilia, although it is not a forced criterion. Its definite diagnosis is anatomopatologic. The steroid use is considered as the angular stone of the treatment. We present two cases, with different clinical presentation forms, with initial answer to steroids and later relapse after the suspension of these, remaining without symptoms actually with dependency of low doses of steroids. Next we will do the revision of the available literature emphasizing the pathophysiologic data, the clinical evaluation and the therapeutic aspects

  14. Gastrointestinal medications and breastfeeding.

    Science.gov (United States)

    Hagemann, T M

    1998-09-01

    Medications used to treat gastrointestinal symptoms are increasingly being used as more have been gained nonprescription status. Most of the gastrointestinal medications, such as laxatives, antacids, and antidiarrheal agents, are used short term. Women who breastfeed should be aware of the risks of taking any medications, whether prescription or nonprescription. There is little information describing transfer into breast milk for many of these products. Cimetidine, atropine, cascara, cisapride, loperamide, magnesium sulfate, and senna are the only products identified by the AAP as compatible with breast feeding. Metoclopramide is listed by the AAP as a drug whose effect on nursing infants is unknown but may be of potential concern, although studies published to date have not reported any adverse effects. The safest laxatives and antidiarrheals are those that are not absorbed and should be considered first-line therapy for conditions of constipation or loose stools. Famotidine and nizatidine are excreted into breast milk to a lesser extent than cimetidine or ranitidine and may be the preferred histamine antagonists. Despite the limited data on the use of cisapride in nursing women, it is considered safe by the AAP and may be preferred over metoclopramide for first-line prescription treatment of heartburn. Although most of these agents appear safe in the nursing infant, caretakers should be aware of the potential adverse reactions that may occur in infants whose mothers require these products.

  15. Gastrointestinal Headache; a Narrative Review

    Directory of Open Access Journals (Sweden)

    Majid T Noghani

    2016-08-01

    Full Text Available There are studies reporting primary headaches to be associated with gastrointestinal disorders, and some report resolution of headache following the treatment of the associated gastrointestinal disorder. Headache disorders are classified by The International Headache Society as primary or secondary; however, among the secondary headaches, those attributed to gastrointestinal disorders are not appreciated. Therefore, we aimed to review the literature to provide evidence for headaches, which originate from the gastrointestinal system. Gastrointestinal disorders that are reported to be associated with primary headaches include dyspepsia, gastro esophageal reflux disease (GERD, constipation, functional abdominal pain, inflammatory bowel syndrome (IBS, inflammatory bowel disorders (IBD, celiac disease, and helicobacter pylori (H. Pylori infection. Some studies have demonstrated remission or improvement of headache following the treatment of the accompanying gastrointestinal disorders. Hypotheses explaining this association are considered to be central sensitization and parasympathetic referred pain, serotonin pathways, autonomic nervous system dysfunction, systemic vasculopathy, and food allergy. Traditional Persian physicians, namely Ebn-e-Sina (Avicenna and Râzi (Rhazes believed in a type of headache originating from disorders of the stomach and named it as an individual entity, the "Participatory Headache of Gastric Origin". We suggest providing a unique diagnostic entity for headaches coexisting with any gastrointestinal abnormality that are improved or cured along with the treatment of the gastrointestinal disorder.

  16. Scintigraphic assessment of gastrointestinal motility

    DEFF Research Database (Denmark)

    Madsen, Jan Lysgård

    2014-01-01

    intestinal and colonic transit. This article reviews current imaging techniques, methods for data processing and principles for evaluating results when scintigraphy is used to assess gastrointestinal motility. Furthermore, clinical indications for performing scintigraphy are reviewed.......Gastrointestinal transit reflects overall gastrointestinal motor activity and is regulated by a complex interplay between neural and hormonal stimuli. Thus, transit measurements provide a measure of the combined effects of gastrointestinal muscular activity and feedback from the gut and brain....... Dysmotility in the different major segments of the gastrointestinal tract may give rise to similar symptoms; hence, localizing transit abnormalities to a specific segment is a valuable element of diagnostic evaluation. Scintigraphy is an effective noninvasive tool to assess gastric emptying as well as small...

  17. Localization of gastrointestinal deposition of mercuric chloride studied in vivo

    International Nuclear Information System (INIS)

    Nielsen, J.B.; Andersen, H.L.; Soerensen, J.A.; Andersen, O.

    1992-01-01

    During the last 5 years, the site of gastrointestinal absorption of inorganic mercury has been attempted identified mainly by experiments using perfused intestinal segments in vitro or in situ. The present investigation will discuss the localization of the absorption site for mercuric chloride based on a completely undisturbed in vivo experimental model in mice. As the mice were allowed to eat their normal diet during the experimental period, the present results would independently add to existing knowledge on intestinal absorption sites for inorganic mercury. The mice were given 203 Hg labelled mercuric chloride orally, either through stomach tube or in the drinking water, and were killed after various time intervals. Mercury was localized and quantified in various segments of the gastrointestinal tract by gamma-counting. Time course analysis of the segmental deposition of mercury demonstrated that the deposition mainly takes place in the proximal jejunum and suggested that a larger part of the jejunum than previously reported is involved in absorption of mercury. Using this in vivo model, tetraethylthiuram disulfide was demonstrated to increase the intestinal deposition and absorption without changing the site of deposition. (au)

  18. The gastrointestinal tract

    DEFF Research Database (Denmark)

    Bartels, Else M.; Harrison, Adrian Paul

    2009-01-01

    The gastrointestinal tract (GIT) has always been and remains a major source of interest in terms of both its function, and its malfunction. Our current knowledge of age-related changes in this system, as well as drug-food interactions, however, remains relatively limited. Paradoxically, the GIT......-related GIT damage and dysfunction. New and novel aspects of drug delivery and drug-dietary supplement interactions are discusses and much needed areas of focus in terms of drug GIT testing are identified....... is not one of the core battery of tests that pharmaceutical companies are obliged to investigate as part of drug development. This review aims to cover the basics of GIT function before highlighting aspects of relevance for safety pharmacology in terms of age, cancerogenesis, and noth drug and diet...

  19. Gastrointestinal infections in children.

    Science.gov (United States)

    Mönkemüller, K E; Wilcox, C M

    2001-01-01

    Gastrointestinal infections in children are a major cause of morbidity and mortality worldwide. Children living in developing countries are particularly susceptible to infectious diarrhea because of poor standards of hygiene and sanitation. Although the magnitude of diarrheal illnesses in developed countries is less, costly hospital admissions are still frequent. The causal agent of infectious diarrhea is most frequently related to age, geographical location, lifestyle habits, use of antibiotics, associated medical conditions, social circumstances, and degree of immune competence. In this article we present some of the most important articles published in the field during the last year. The role of Helicobacter pylori in the pathogenesis of gastritis and peptic ulcer disease has been shown in adults and children. Information about the natural history of H. pylori, symptomatology, and diagnostic therapeutic approaches for children are being generated constantly; we discuss some of the most relevant information in this review.

  20. Estrogen and gastrointestinal malignancy.

    LENUS (Irish Health Repository)

    Hogan, A M

    2012-02-01

    The concept that E2 exerts an effect on the gastrointestinal tract is not new and its actions on intestinal mucosa have been investigated for at least three decades. An attempt to consolidate results of these investigations generates more questions than answers, thus suggesting that many unexplored avenues remain and that the full capabilities of this steroid hormone are far from understood. Evidence of its role in esophageal, gastric and gallbladder cancers is confusing and often equivocal. The most compelling evidence regards the protective role conferred by estrogen (or perhaps ERbeta) against the development and proliferation of colon cancer. Not only has the effect been described but also many mechanisms of action have been explored. It is likely that, along with surgery, chemotherapy and radiotherapy, hormonal manipulation will play an integral role in colon cancer management in the very near future.

  1. Lower gastrointestinal malignancies

    International Nuclear Information System (INIS)

    Minsky, Bruce D.

    1995-01-01

    Objective: This refresher course will review the current knowledge as well as ongoing and future research strategies in lower gastrointestinal malignancies. Radiation therapy has a significant role in the adjuvant treatment of lower gastrointestinal malignancies. Furthermore, there are data to suggest that radiation therapy is an integral component of the conservative management (organ preservation) of rectal and anal cancers. 1. Colon cancer. The standard adjuvant treatment for node positive or high risk transmural colon cancer is postoperative 5-FU and Levamisole. There are retrospective data to suggest that certain subsets of high risk patients may benefit from postoperative radiation therapy. 2. Rectal cancer. Randomized trials have revealed an advantage of postoperative radiation therapy plus chemotherapy in transmural and/or node positive rectal cancer. In the adjuvant setting the use of continuous infusion 5-FU may be more beneficial compared with bolus 5-FU. Despite the improvement in survival, postoperative therapies are associated with an approximately 35% incidence of grade 3+ toxicity. Recent data suggest that the use of preoperative combined modality therapy may be associated with less toxicity as well as increase the chance of sphincter preservation. New Intergroup trials addressing these issues will be presented. In patients with locally advanced unresectable rectal cancer, the addition of intraoperative radiation therapy may further improve local control. 3. Anal cancer. The use of combined 5-FU/Mitomycin-C and pelvic radiation therapy is effective in the treatment of anal carcinoma. The RTOG has recently completed a randomized trial addressing the question of the effectiveness and toxicity of Mitomycin-C. The replacement Intergroup Phase III trial will be presented

  2. Stromal gastrointestinal tumors (GIST)

    International Nuclear Information System (INIS)

    Balev, B.; Boykova, K.

    2015-01-01

    Full text: GIST are a heterogeneous group of mesenchymal tumors of the gastrointestinal tract with varying tumor grade and frequency of 1: 100 000 per year. Mazur and Clark introduced the term for the first time in 1983. GIST constitute approximately 2% of the tumors in the gastrointestinal tract. The average age is 60 years. The most common locations are the stomach (60%), small intestine (30%), esophagus (1%), and rectum (5%). Learning objective: to demonstrate the imaging characteristics of the disease according to the current ESMO guidelines and to present the diagnostic accuracy of different imaging modalitiesnbased on review of literature and on own observations. GIST originate from interstitial cells (of Cajal) in the GIT wall, belonging to the autonomic nervous system, which is responsible for motility. 90% of GIST show overexpression of the KIT receptor, also known as CD117 or stem cell factor receptor. those that do not express c-KIT mutations, activate mutations in PDGFRA gene. Tumor’s macromorphology determines the imaging features on different modalities. Most of these tumors are exophytic, subepithelial, reach large size and enhance inhomogeneous due to necrosis. They usually do not cause obstruction. Ultrasound as the initiation method shows low sensitivity and specificity in GIST detection, CT with intravenous contrast is the gold standard. MRI contributes with assessing the vascularisation, cellularity and pH. FDG-PET/CT registers the metabolism of intratumoral acidosis. CT is the method of choice in the early diagnosis and determination of resectability of GIST. MRI is an additional method. PET FDG-CT is useful for the monitoring of patients treated with Imatinib

  3. Lower gastrointestinal malignancies

    International Nuclear Information System (INIS)

    Minsky, Bruce D.

    1996-01-01

    Objective: This refresher course will review the current knowledge as well as ongoing and future research strategies in lower gastrointestinal malignancies. Radiation therapy has a significant role in the adjuvant treatment of lower gastrointestinal malignancies. Furthermore, there are data to suggest that radiation therapy is an integral component of the conservative management (organ preservation) of rectal and anal cancers. 1. Colon cancer. The standard adjuvant treatment for node positive or high risk transmural colon cancer is postoperative 5-FU and Levamisole. There are retrospective data to suggest that certain subsets of high risk patients may benefit from postoperative radiation therapy. 2. Rectal cancer. Randomized trials have revealed an advantage of postoperative radiation therapy plus chemotherapy in transmural and/or node positive rectal cancer. In the adjuvant setting the use of continuous infusion 5-FU may be more beneficial compared with bolus 5-FU. Despite the improvement in survival, postoperative therapies are associated with an approximately 35% incidence of grade 3+ toxicity. Recent data suggest that the use of preoperative combined modality therapy may be associated with less toxicity as well as increase the chance of sphincter preservation. New Intergroup trials addressing these issues will be presented. In patients with locally advanced unresectable rectal cancer, the addition of intraoperative radiation therapy may further improve local control. 3. Anal cancer. The use of combined 5-FU/Mitomycin-C and pelvic radiation therapy is effective in the treatment of anal carcinoma. The RTOG has recently completed a randomized trial addressing the question of the effectiveness and toxicity of Mitomycin-C. The replacement Intergroup Phase III trial will be presented

  4. Mystery Fractions

    Science.gov (United States)

    Bhattacharyya, Sonalee; Namakshi, Nama; Zunker, Christina; Warshauer, Hiroko K.; Warshauer, Max

    2016-01-01

    Making math more engaging for students is a challenge that every teacher faces on a daily basis. These authors write that they are constantly searching for rich problem-solving tasks that cover the necessary content, develop critical-thinking skills, and engage student interest. The Mystery Fraction activity provided here focuses on a key number…

  5. [Important application of intestinal transporters and metabolism enzymes on gastrointestinal disposal of active ingredients of Chinese materia medica].

    Science.gov (United States)

    Bi, Xiaolin; Du, Qiu; Di, Liuqing

    2010-02-01

    Oral drug bioavailability depends on gastrointestinal absorption, intestinal transporters and metabolism enzymes are the important factors in drug gastrointestinal absorption and they can also be induced or inhibited by the active ingredients of Chinese materia medica. This article presents important application of intestinal transporters and metabolism enzymes on gastrointestinal disposal of the active ingredients of Chinese materia medica, and points out the importance of research on transport and metabolism of the active ingredients of Chinese materia medica in Chinese extract and Chinese medicinal formulae.

  6. Arsenic speciation in total contents and bioaccessible fractions in atmospheric particles related to human intakes

    International Nuclear Information System (INIS)

    Huang, Minjuan; Chen, Xunwen; Zhao, Yinge; Yu Chan, Chuen; Wang, Wei; Wang, Xuemei; Wong, Ming Hung

    2014-01-01

    Speciation of inorganic trivalent arsenicals (iAs III ), inorganic pentavalent arsenicals (iAs V ), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) in total arsenic (As) content and its bioaccessible fractions contained in road dust, household air-conditioning (AC) filter dust and PM 2.5 was investigated. Inorganic As, especially iAs V , was observed as the dominant species. Physiologically based extraction test (PBET), an in-vitro gastrointestinal method, was used to estimate the oral As bioaccessibility in coarse particles and the species present in the oral bioaccessible fraction. A composite lung simulating serum was used to mimic the pulmonary condition to extract the respiratory bioaccessible As and its species in PM 2.5 . Reduction of iAs V to iAs III occurred in both in-vitro gastrointestinal and lung simulating extraction models. The inorganic As species was the exclusive species for absorption through ingestion and inhalation of atmospheric particles, which was an important exposure route to inorganic As, in addition to drinking water and food consumption. - Highlights: • Inorganic As species was the predominant species in dust and airborne particles. • Existence of iAs III in dust and airborne particles increases human health risks. • Reduction from iAs V to iAs III occurred through in-vitro gastrointestinal model. • Reduction from iAs V to iAs III occurred in the simulating pulmonary region. • Atmospheric particles were important exposure sources of inorganic As. - Atmospheric particles are important exposure sources of inorganic As, of which the bioaccessibility is dependent on the extraction phases and models used

  7. Fraction Reduction through Continued Fractions

    Science.gov (United States)

    Carley, Holly

    2011-01-01

    This article presents a method of reducing fractions without factoring. The ideas presented may be useful as a project for motivated students in an undergraduate number theory course. The discussion is related to the Euclidean Algorithm and its variations may lead to projects or early examples involving efficiency of an algorithm.

  8. Alkali absorption and citrate excretion in calcium nephrolithiasis

    Science.gov (United States)

    Sakhaee, K.; Williams, R. H.; Oh, M. S.; Padalino, P.; Adams-Huet, B.; Whitson, P.; Pak, C. Y.

    1993-01-01

    The role of net gastrointestinal (GI) alkali absorption in the development of hypocitraturia was investigated. The net GI absorption of alkali was estimated from the difference between simple urinary cations (Ca, Mg, Na, and K) and anions (Cl and P). In 131 normal subjects, the 24 h urinary citrate was positively correlated with the net GI absorption of alkali (r = 0.49, p origin of hypocitraturia. However, the normal dependence was maintained in CDS and in idiopathic hypocitraturia, suggesting that reduced citrate excretion was largely dietary in origin as a result of low net alkali absorption (from a probable relative deficiency of vegetables and fruits or a relative excess of animal proteins).

  9. Phytochemistry and gastrointestinal benefits of the medicinal spice, Capsicum annuum L. (Chilli): a review.

    Science.gov (United States)

    Maji, Amal K; Banerji, Pratim

    2016-06-01

    Dietary spices and their active constituents provide various beneficial effects on the gastrointestinal system by variety of mechanisms such as influence of gastric emptying, stimulation of gastrointestinal defense and absorption, stimulation of salivary, intestinal, hepatic, and pancreatic secretions. Capsicum annuum (Solanaceae), commonly known as chilli, is a medicinal spice used in various Indian traditional systems of medicine and it has been acknowledged to treat various health ailments. Therapeutic potential of chilli and capsaicin were well documented; however, they act as double-edged sword in many physiological circumstances. In traditional medicine chilli has been used against various gastrointestinal complains such as dyspepsia, loss of appetite, gastroesophageal reflux disease, gastric ulcer, and so on. In chilli, more than 200 constituents have been identified and some of its active constituents play numerous beneficial roles in various gastrointestinal disorders such as stimulation of digestion and gastromucosal defense, reduction of gastroesophageal reflux disease (GERD) symptoms, inhibition of gastrointestinal pathogens, ulceration and cancers, regulation of gastrointestinal secretions and absorptions. However, further studies are warranted to determine the dose ceiling limit of chilli and its active constituents for their utilization as gastroprotective agents. This review summarizes the phytochemistry and various gastrointestinal benefits of chilli and its various active constituents.

  10. Fractional decay of quantum dots in photonic crystals

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Koenderink, Femius; Lodahl, Peter

    2008-01-01

    We define a practical measure for the degree of fractional decay and establish conditions for the effect to be observable for quantum dots in photonic crystals exhibiting absorptive losses.......We define a practical measure for the degree of fractional decay and establish conditions for the effect to be observable for quantum dots in photonic crystals exhibiting absorptive losses....

  11. Gastrointestinal nuclear medicine

    International Nuclear Information System (INIS)

    Koblik, P.D.; Hornof, W.J.

    1985-01-01

    General localization of gastrointestinal bleeding through the use of labeled red blood cells may be performed in children, or (99m)Tc-pertechnetate may be used if a Meckel's diverticulum is suspected. As in adults, cholecystitis and biliary leak may be assessed in children via (99m)Tc-IDA derivatives. Gastroesophageal reflux can be evaluated by oral consumption of the child's usual diet labeled with (99m)Tc sulfur colloid. For the scintigraphic determination of pulmonary aspiration, a relatively high concentration of tracer within a drop of liquid is placed beneath the child's tongue followed by dynamic imaging of the respiratory tract. Colonic transit scintigraphy can aid in the identification and therapeutic decision-making in patients with functional fecal retention, the most common cause of chronic constipation in children. (18)F-DOPA positron emission tomography is useful for classifying pancreatic involvement in infantile hyperinsulinism as focal or diffuse, thereby differentiating between patients who should receive curative focal pancreatic resection versus those who should receive medical management. Assessment of protein-losing enteropathy can be conducted scintigraphically and, compared with fecal alpha-1 antitrypsin collection, the scintigraphic method can detect esophageal and gastric protein loss. Also, scintigraphic quantification of protein loss can be performed without the requirement for fecal collection. Intestinal inflammation in children with inflammatory bowel disease can be evaluated using (99m)Tc white blood cells. The scintigraphic method is safe, accurate, well-tolerated by children and complementary to endoscopy in most patients

  12. Gastrointestinal scanning agent

    International Nuclear Information System (INIS)

    Francis, M.D.

    1980-01-01

    An easily prepared radiolabeled gastrointestinal scanning agent is described. Technetium-99m has ideal characteristics for imaging the upper and lower GI tract and determining stomach emptying and intestinal transit time when used with an insoluble particulate material. For example, crystalline and amorphous calcium phosphate particles can be effectively labeled in a one-step process using sup(99m)TcO 4 and SnCl 2 . These labeled particles have insignificant mass and when administered orally pass through the GI tract unchanged, without affecting the handling and density of the intestinal contents. Visualization of the esophageal entry into the stomach, the greater and lesser curvatures of the stomach, ejection into the duodenum, and rates of passage through the upper and lower GI tract are obtained. The slurry of sup(99m)TC particulate can be given rectally by enema. Good images of the cecum and the ascending, transverse, and descending colon are obtained. Mucosal folds and the splenic and hepatic flexures are visualized. The resilience of the large intestine is also readily visualized by pneumocolonographic techniques. (author)

  13. Scintigraphic evaluation of gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Park, Yong Tai; Lee, Choon Keun; Lee, Sun Wha; Choi, Woo Suk; Yoon, Yup; Lim, Jae Hoon

    1988-01-01

    Gastrointestinal bleeding remains a major diagnostic problem. Although advances have been made in the medical and surgical methods of managing gastrointestinal bleeding, the commonly employed techniques of barium radiography, endoscopy, and angiography may not successfully localize the site and define the cause of gastrointestinal bleeding. Two widely available technetium-99m-labeled radiopharmaceuticals, sulfur colloid and red blood cells are currently used in the evaluation of patients who are bleeding from the gastrointestinal tract. Surgically confirmed 19 patients with use of 99m Tc-sulfur colloid (7 cases) and 99m Tc-RBC (12 cases) were retrospectively evaluated. The overall sensitivity of scintigraphy in detection of bleeding and localization of bleeding site was 68% and 84%, respectively. The authors conclude that bleeding scintigraphy is a safe, sensitive, and non-invasive method as an effective screening test before performing angiography or surgery.

  14. Sleep Dysfunction and Gastrointestinal Diseases.

    Science.gov (United States)

    Khanijow, Vikesh; Prakash, Pia; Emsellem, Helene A; Borum, Marie L; Doman, David B

    2015-12-01

    Sleep deprivation and impaired sleep quality have been associated with poor health outcomes. Many patients experience sleep disturbances, which can increase the risk of medical conditions such as hypertension, obesity, stroke, and heart disease as well as increase overall mortality. Recent studies have suggested that there is a strong association between sleep disturbances and gastrointestinal diseases. Proinflammatory cytokines, such as tumor necrosis factor, interleukin-1, and interleukin-6, have been associated with sleep dysfunction. Alterations in these cytokines have been seen in certain gastrointestinal diseases, such as gastroesophageal reflux disease, inflammatory bowel disease, liver disorders, and colorectal cancer. It is important for gastroenterologists to be aware of the relationship between sleep disorders and gastrointestinal illnesses to ensure good care for patients. This article reviews the current research on the interplay between sleep disorders, immune function, and gastrointestinal diseases.

  15. Radiological Atlas of Gastrointestinal Disease

    International Nuclear Information System (INIS)

    Nolan, D.J.

    1983-01-01

    This book is a reference to gastrointestinal disease and radiographic methods. It provides complete information for diagnosis and management and includes coverage of plain radiography, barium studies, water-soluble contrast studies, and more

  16. GASTROINTESTINAL INJURIES FROM BLUNT ABDOMINAL ...

    African Journals Online (AJOL)

    hi-tech

    2004-04-04

    Apr 4, 2004 ... Subjects: Twenty one children managed for gastrointestinal injuries from blunt trauma ... ileus, urinary tract infection and chest infection, respectively postoperatively. .... predictive value with CT scan, (9) the positive predictive.

  17. CT of acute gastrointestinal disease

    International Nuclear Information System (INIS)

    Wittenberg, J.

    1991-01-01

    The application of computerized tomography in gastrointestinal tract diseases are presented, including advantages in surgical belly that are: anatomic clarity, wide survey and rapid performance. (C.G.C.)

  18. Bioactive protein fraction DLBS1033 containing lumbrokinase isolated from Lumbricus rubellus: ex vivo, in vivo, and pharmaceutic studies

    Directory of Open Access Journals (Sweden)

    Tjandrawinata RR

    2014-09-01

    Full Text Available Raymond R Tjandrawinata,1 Jessica Trisina,1 Puji Rahayu,1 Lorentius Agung Prasetya,1 Aang Hanafiah,2 Heni Rachmawati3 1Dexa Laboratories of Biomolecular Sciences, Dexa Medica, Cikarang, Indonesia; 2National Nuclear Energy Agency, Bandung, Indonesia; 3School of Pharmacy, Bandung Institute of Technology, Bandung, Indonesia Abstract: DLBS1033 is a bioactive protein fraction isolated from Lumbricus rubellus that tends to be unstable when exposed to the gastrointestinal environment. Accordingly, appropriate pharmaceutical development is needed to maximize absorption of the protein fraction in the gastrointestinal tract. In vitro, ex vivo, and in vivo stability assays were performed to study the stability of the bioactive protein fraction in gastric conditions. The bioactive protein fraction DLBS1033 was found to be unstable at low pH and in gastric fluid. The “enteric coating” formulation showed no leakage in gastric fluid–like medium and possessed a good release profile in simulated intestinal medium. DLBS1033 was absorbed through the small intestine in an intact protein form, confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE analysis. This result confirmed that an enteric coating formula using methacrylic acid copolymer could protect DLBS1033 from the acidic condition of the stomach by preventing the release of DLBS1033 in the stomach, while promoting its release when reaching the intestine. From the blood concentration–versus-time curve, 99mTc-DLBS1033 showed a circulation half-life of 70 minutes. This relatively long biological half-life supports its function as a thrombolytic protein. Thus, an enteric delivery system is considered the best approach for DLBS1033 as an oral thrombolytic agent. Keywords: bioactive protein fraction, enteric coated tablet, pharmacodynamic

  19. A reaction limited in vivo dissolution model for the study of drug absorption: Towards a new paradigm for the biopharmaceutic classification of drugs.

    Science.gov (United States)

    Macheras, Panos; Iliadis, Athanassios; Melagraki, Georgia

    2018-05-30

    The aim of this work is to develop a gastrointestinal (GI) drug absorption model based on a reaction limited model of dissolution and consider its impact on the biopharmaceutic classification of drugs. Estimates for the fraction of dose absorbed as a function of dose, solubility, reaction/dissolution rate constant and the stoichiometry of drug-GI fluids reaction/dissolution were derived by numerical solution of the model equations. The undissolved drug dose and the reaction/dissolution rate constant drive the dissolution rate and determine the extent of absorption when high-constant drug permeability throughout the gastrointestinal tract is assumed. Dose is an important element of drug-GI fluids reaction/dissolution while solubility exclusively acts as an upper limit for drug concentrations in the lumen. The 3D plots of fraction of dose absorbed as a function of dose and reaction/dissolution rate constant for highly soluble and low soluble drugs for different "stoichiometries" (0.7, 1.0, 2.0) of the drug-reaction/dissolution with the GI fluids revealed that high extent of absorption was found assuming high drug- reaction/dissolution rate constant and high drug solubility. The model equations were used to simulate in vivo supersaturation and precipitation phenomena. The model developed provides the theoretical basis for the interpretation of the extent of drug's absorption on the basis of the parameters associated with the drug-GI fluids reaction/dissolution. A new paradigm emerges for the biopharmaceutic classification of drugs, namely, a model independent biopharmaceutic classification scheme of four drug categories based on either the fulfillment or not of the current dissolution criteria and the high or low % drug metabolism. Copyright © 2018. Published by Elsevier B.V.

  20. Drug therapy for gastrointestinal and liver diseases

    National Research Council Canada - National Science Library

    Ballinger, Anne; Farthing, M. J. G. (Michael J. G.)

    2001-01-01

    ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Gastrointestinal bleeding Matthew R Banks, Peter D Fairclough . . . . . . . . . . . . . . . . . . . . 63 Inflammatory bowel...

  1. Antioxidant supplements for preventing gastrointestinal cancers

    DEFF Research Database (Denmark)

    Bjelakovic, G; Nikolova, D; Simonetti, R G

    2004-01-01

    Oxidative stress may cause gastrointestinal cancers. The evidence on whether antioxidant supplements are effective in preventing gastrointestinal cancers is contradictory.......Oxidative stress may cause gastrointestinal cancers. The evidence on whether antioxidant supplements are effective in preventing gastrointestinal cancers is contradictory....

  2. Assessing the zearalenone-binding activity of adsorbent materials during passage through a dynamic in vitro gastrointestinal model

    NARCIS (Netherlands)

    Avantaggiato, G.; Havenaar, R.; Visconti, A.

    2003-01-01

    A novel approach is presented herein to study the intestinal absorption of mycotoxins by using a laboratory model that mimics the metabolic processes of the gastrointestinal (GI) tract of healthy pigs. This model was used to evaluate the small-intestinal absorption of zearalenone from contaminated

  3. Foreign bodies in gastrointestinal tract

    Directory of Open Access Journals (Sweden)

    Ayşe Kefeli

    2014-03-01

    Full Text Available Objective: Ingested foreign bodies in gastrointestinal tract are a common event which can cause serious morbidity and mortality in the children and adult population. For this reason, early diagnosis and treatment are crucial for preventing these life threatening complications. In this study, we aimed to analyze the characteristics of the patients with upper gastrointestinal foreign bodies that were treated in our department. Methods: Patients diagnosed with upper gastrointestinal foreign bodies who were admitted to our hospital between February 2010 and August2013 were evaluated retrospectively. The data regarding their age, gender, clinical profile, type and localization of the esophageal foreign body, performed endoscopic procedure and initial symptoms of the patients were noted and analyzed statistically. Results: Thirty-eight patients with a diagnosis of gastrointestinal foreign body were included in this study. Of these patients, 21 were male and 17 were female. The youngest patient was 17 years old and the oldest patient was 79 years old. Most of the foreign bodies (%55.3 detected in the stomach. Food waste and metallic objects in 21 and 16 patients respectively. The most common complaint was dysphagia (%50. After endoscopic intervention three of the patients were directed to surgery. Conclusion: Early recognition and treatment of gastrointestinal foreign bodies is important as their complications are life threatening. The best method of removal of foreign bodies is controversial. Early management with upper gastrointestinal endoscopy is the most efficient and safe treatment method in current conditions.

  4. Fluoride absorption: independence from plasma fluoride levels

    International Nuclear Information System (INIS)

    Whitford, G.M.; Williams, J.L.

    1986-01-01

    The concept that there are physiologic mechanisms to homeostatically regulate plasma fluoride concentrations has been supported by results in the literature suggesting an inverse relationship between plasma fluoride levels and the absorption of the ion from the gastrointestinal tract of the rat. The validity of the relationship was questioned because of possible problems in the experimental design. The present work used four different methods to evaluate the effect of plasma fluoride levels on the absorption of the ion in rats: (i) the percentage of the daily fluoride intake that was excreted in the urine; (ii) the concentration of fluoride in femur epiphyses; (iii) the net areas under the time-plasma fluoride concentration curves after intragastric fluoride doses; and (iv) the residual amounts or fluoride in the gastrointestinal tracts after the intragastric fluoride doses. None of these methods indicated that plasma fluoride levels influence the rate or the degree or fluoride absorption. It was concluded that, unless extremely high plasma fluoride levels are involved (pharmacologic or toxic doses), the absorption of the ion is independent of plasma levels. The results provide further evidence that plasma fluoride concentrations are not homeostatically regulated

  5. Insights into Digestion and Absorption of Major Nutrients in Humans

    Science.gov (United States)

    Goodman, Barbara E.

    2010-01-01

    Nutrient digestion and absorption is necessary for the survival of living organisms and has evolved into the complex and specific task of the gastrointestinal (GI) system. While most people simply assume that their GI tract will work properly to use nutrients, provide energy, and release wastes, few nonscientists know the details about how various…

  6. Fractionation and immunochemical characterization of Prosopis juliflora pollen allergen.

    Science.gov (United States)

    Thakur, I S

    1986-12-01

    Prosopis juliflora pollen grain crude extract gave six different molecular weight fractions varied from 81,000 to 13,000 dalton on Sephadex G-100 gel filtration. The purity of fractions of Prosopis juliflora pollen extract were checked by polyacrylamide gel electrophoresis. The fraction had an molecular weight 20,000 dalton showed four absorption maxima whereas other fractions had single absorption maxima. Allergenic activity and nature of allergens were evaluated by in vitro Radioallergosorbent test and in vivo Passive Cutaneous Anaphylaxis test. All these tests indicated that most allergenic fractions were in the 20,000 molecular weight.

  7. The effects of Co60 gamma rays on the absorption of salicylic natrium orally given to white rats

    International Nuclear Information System (INIS)

    Wiharto, Kunto; Kamal, Zainul; Mulyanto; Muryono, H.

    1982-01-01

    The effects of Co 60 gamma rays on the absorption of salicylic natrium orally taken by white rats after being irradiated were studied. Patients treated with radiation used to be given analgesic drugs to elicit pain. Effects of radiation on the physiology of gastrointestinal tracts of such patients are to be studied. Based on this perception some white rats were irradiated with Co 60 gamma rays at the cumulative doses of 500, 750, and 1000 rads which were fractionated to 5 daily doses of 100, 150, and 200 rads. Salicylate concentration in the rat's blood was measured with spectrophotometer. It was found that the greater the radiation dose was given, the less salicylic natrium was absorbed and at a certain dose saturation point happened. (RUW)

  8. Gastrointestinal Motility Variation and Implications for Plasma Level Variation: Oral Drug Products.

    Science.gov (United States)

    Talattof, Arjang; Price, Judy C; Amidon, Gordon L

    2016-02-01

    The oral route of administration is still by far the most ubiquitous method of drug delivery. Development in this area still faces many challenges due to the complexity and inhomogeneity of the gastrointestinal environment. In particular, dosing unpredictably relative to motility phase means the gastrointestinal environment is a random variable within a defined range. Here, we present a mass balance analysis that captures this variation and highlights the effects of gastrointestinal motility, exploring what impacts it ultimately has on plasma levels and the relationship to bioequivalence for high solubility products with both high and low permeability (BCS I and III). Motility-dependent compartmental absorption and transit (MDCAT) mechanistic analysis is developed to describe the underlying fasted state cyclical motility and how the contents of the gastrointestinal tract are propelled.

  9. A prebiotic fiber increases the formation and subsequent absorption of compound K following oral administration of ginseng in rats

    Directory of Open Access Journals (Sweden)

    Kyung-Ah Kim

    2015-04-01

    Conclusion: These results show that prebiotic diets, such as NUTRIOSE, may promote the metabolic conversion of ginsenosides to CK and the subsequent absorption of CK in the gastrointestinal tract and may potentiate the pharmacological effects of ginseng.

  10. Fractional vector calculus for fractional advection dispersion

    Science.gov (United States)

    Meerschaert, Mark M.; Mortensen, Jeff; Wheatcraft, Stephen W.

    2006-07-01

    We develop the basic tools of fractional vector calculus including a fractional derivative version of the gradient, divergence, and curl, and a fractional divergence theorem and Stokes theorem. These basic tools are then applied to provide a physical explanation for the fractional advection-dispersion equation for flow in heterogeneous porous media.

  11. Nutritional status and related factors of patients with advanced gastrointestinal cancer.

    Science.gov (United States)

    Zhang, Liyan; Lu, Yuhan; Fang, Yu

    2014-04-14

    The scored Patient-Generated Subjective Global Assessment (PG-SGA) is considered to be the most appropriate tool for detecting malnutrition in cancer patients. In particular, malignant tumours derived from the gastrointestinal tract may impair nutrient intake and absorption and cause malnutrition. We carried out a cross-sectional study to assess the nutritional status and related factors of patients with gastrointestinal cancer. Nutritional status was determined using the scored PG-SGA in patients (n 498) with advanced gastrointestinal cancer admitted to the Gastrointestinal Medical Oncology Unit at Beijing Cancer Hospital between 1 August 2012 and 28 February 2013. The possible related factors including age, sex, hospitalisation frequency and pathology were explored. We found that 98% of the patients required nutrition intervention and 54% of the patients required improved nutrition-related symptom management and/or urgent nutritional support (PG-SGA score ≥9). Factors related to malnutrition were age (r 0.103, Pcancer had a lower risk of malnutrition than patients with other types of gastrointestinal cancer (F=35.895, Pnutritional status of gastrointestinal patients, especially those at a higher risk of malnutrition, such as elderly patients, those hospitalised for the first time, male patients and those with other types of gastrointestinal cancer except rectal cancer. The nutritional status of these patients should be evaluated and they should be given proper nutrition education and nutritional support in a timely manner.

  12. Fractional Schroedinger equation

    International Nuclear Information System (INIS)

    Laskin, Nick

    2002-01-01

    Some properties of the fractional Schroedinger equation are studied. We prove the Hermiticity of the fractional Hamilton operator and establish the parity conservation law for fractional quantum mechanics. As physical applications of the fractional Schroedinger equation we find the energy spectra of a hydrogenlike atom (fractional 'Bohr atom') and of a fractional oscillator in the semiclassical approximation. An equation for the fractional probability current density is developed and discussed. We also discuss the relationships between the fractional and standard Schroedinger equations

  13. Scintigraphic evaluation of gastrointestinal motility disorders

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Jae Gol [College of Medicine, Korea Univ., Seoul (Korea, Republic of)

    2001-02-01

    Current scintigraphic tests of gastrointestinal motor function provides relevant pathophysiologic information, but their clinical utility is controversial. Many scintigraphic methods are developed to investigate gastrointestinal motility from oral cavity to colon. These are esophageal transit scintigraphy, oropharyngeal transit study, gastric emptying test, small bowel transit time measurement, colon transit study and gastroesopahgeal reflux scintigraphy. Scintigraphy of gastrointestinal tract is the most physiologic and noninvasive method to evaluate gastrointestinal motility disorders. Stomach emptying test is regarded as a gold standard in motility study. Gastrointestinal transit scintigraphy also has a certain role in assessment of drug effect to GI motility and changes after theraphy of motility disorders. Scintigraphy provides noninvasive and quantitative assessment of physiological transit throughout the gastrointestinal tract, and it is extremely useful for diagnosing gastrointestinal motor dysfunction. This article reviews the current procedures, indications, significance and guidelines for gastrointestinal motility measurements by scintigraphy.

  14. Scintigraphic evaluation of gastrointestinal motility disorders

    International Nuclear Information System (INIS)

    Choe, Jae Gol

    2001-01-01

    Current scintigraphic tests of gastrointestinal motor function provides relevant pathophysiologic information, but their clinical utility is controversial. Many scintigraphic methods are developed to investigate gastrointestinal motility from oral cavity to colon. These are esophageal transit scintigraphy, oropharyngeal transit study, gastric emptying test, small bowel transit time measurement, colon transit study and gastroesopahgeal reflux scintigraphy. Scintigraphy of gastrointestinal tract is the most physiologic and noninvasive method to evaluate gastrointestinal motility disorders. Stomach emptying test is regarded as a gold standard in motility study. Gastrointestinal transit scintigraphy also has a certain role in assessment of drug effect to GI motility and changes after theraphy of motility disorders. Scintigraphy provides noninvasive and quantitative assessment of physiological transit throughout the gastrointestinal tract, and it is extremely useful for diagnosing gastrointestinal motor dysfunction. This article reviews the current procedures, indications, significance and guidelines for gastrointestinal motility measurements by scintigraphy

  15. Gastrointestinal Carcinoid Tumors—Health Professional Version

    Science.gov (United States)

    Gastrointestinal carcinoid tumors are rare, slow-growing tumors that originate in the neuroendocrine cells in the GI tract. Find evidence-based information on gastrointestinal carcinoid tumors treatment and research.

  16. GASTROINTESTINAL FOOD ALLERGY IN CHILDREN

    Directory of Open Access Journals (Sweden)

    Svetlana G. Makarova

    2017-01-01

    Full Text Available In recent years, there has been a significant increase in the prevalence  of food allergies. Pathological conditions associated  with a food intolerance are becoming an increasingly urgent problem of pediatrics. According to different researchers, allergic lesions of the gastrointestinal tract occurs in 25–50% of patients with such common pathology as an allergy to cow's milk proteins. The severity of diseases  associated  with food allergies and their prognosis  depend largely on early diagnosis and adequate treatment. Difficulties and errors  in the diagnosis  of gastrointestinal  food allergies  are associated  with both subjective  and objective  reasons,  primarily due to the fact that gastrointestinal  reactions to food are often delayed and non-IgE-mediated. The article describes clinical forms of gastrointestinal food allergy according to the existing classification. Diagnostic algorithms and modern approaches  to differential diagnosis of disease based on evidence-based  medicine and corresponding to international consensus papers are given.

  17. GASTROINTESTINAL TRACT OF CLARIAS GARIEPINUS ...

    African Journals Online (AJOL)

    DR. AMINU

    one hundred and ninety nine (199) were infested fish samples from gills and gastrointestinal tract .... Body cavity of fish were dissected using a pair of scissors and different portion of the gut (Oesophagus, stomach, intestine and rectum) were isolated and kept in .... Arme, C. and Wakey, M. (1970): The physiology of fishes.

  18. Nutritional management of gastrointestinal malignancies ...

    African Journals Online (AJOL)

    The evidence connecting food and gastrointestinal cancers from epidemiological studies, case-control studies, and prospective observational studies, indicates that determining the independent effects of specific nutrients is extremely diffi cult, given the many potential environmental factors to consider. The nutritional ...

  19. Approach to upper gastrointestinal bleeding

    African Journals Online (AJOL)

    Upper gastrointestinal haemorrhage has a variety of causes (Table 1) and is the commonest complication of peptic ulceration and portal hypertension. Peptic ulceration in the duo- denum or stomach and oesophageal varices are the conditions most often responsible for patients who have the potential to present.

  20. Immunity to gastrointestinal nematode infections

    DEFF Research Database (Denmark)

    Sorobetea, D.; Svensson Frej, M.; Grencis, R.

    2018-01-01

    Numerous species of nematodes have evolved to inhabit the gastrointestinal tract of animals and humans, with over a billion of the world's population infected with at least one species. These large multicellular pathogens present a considerable and complex challenge to the host immune system give...

  1. Meadow based Fraction Theory

    OpenAIRE

    Bergstra, Jan A.

    2015-01-01

    In the context of an involutive meadow a precise definition of fractions is formulated and on that basis formal definitions of various classes of fractions are given. The definitions follow the fractions as terms paradigm. That paradigm is compared with two competing paradigms for storytelling on fractions: fractions as values and fractions as pairs.

  2. Gastrointestinal Stromal Tumors: A Case Report

    OpenAIRE

    Sashidharan, Palankezhe; Matele, Apoorva; Matele, Usha; Al Felahi, Nowfel; Kassem, Khalid F.

    2014-01-01

    Advances in the identification of gastrointestinal stromal tumors, its molecular and immunohiostochemical basis, and its management have been a watershed in the treatment of gastrointestinal tumors. This paradigm shift occurred over the last two decades and gastrointestinal stromal tumors have now come to be understood as rare gastrointestinal tract tumors with predictable behavior and outcome, replacing the older terminologies like leiomyoma, schwannoma or leiomyosarcoma. This report present...

  3. Tumor del estroma gastrointestinal Tumor of the gastrointestinal stroma

    Directory of Open Access Journals (Sweden)

    Jorge Felipe Montero León

    2012-03-01

    Full Text Available Los tumores del estroma gastrointestinal, conocidos según sus siglas en inglés como GIST (gastrointestinal stromal tumors, son tumores mesenquimales que aparecen en cualquier lugar a lo largo del tracto intestinal. Este trabajo tiene el propósito de presentar una paciente de 60 años de edad que asiste a la consulta de ginecología del Instituto Nacional de Oncología y Radiobiología, por presentar dolor en el epigastrio, que se irradia al flanco derecho, con un aumento de volumen en la fosa iliaca derecha, y por ultrasonografía se plantea un tumor de ovario derecho, que se proyecta hacia el epigastrio y a hipocondrio derecho. Se describe la intervención quirúrgica y los hallazgos encontrados en estudios macro y microscópicos, así como en estudios posteriores por inmunohistoquímica de la lesión. Se concluye con un diagnóstico de tumor del estroma gastrointestinal y los resultados de las intervenciones quirúrgicas y medicamentosas realizadas. Se recomienda valorar la importancia de una estrecha relación entre cirujanos generales y ginecólogos frente a enfermedades inesperadas, por su difícil diagnóstico preoperatorio, que conllevan a un tratamiento quirúrgico adecuado, y que por la complejidad que requieren, necesitan de la competencia de ambas especialidades quirúrgicas.The tumors of the gastrointestinal stroma, known in English language as GIST (gastrointestinal stromal tumors are mesenchymal tumors appearing in any place throughout the intestinal tract. The objective of present paper is to present the case of a female patient aged 60 came to Genecology consultation of the National Institute of Oncology and Radiobiology due pain in epigastrium irradiating to right flank with increase of volume in the right iliac fossa and by ultrasonography it is a tumor of right ovarium projecting to epigastrium and the right hypochondrium. The surgical intervention is described as well as the findings noted in macro- and microscopic studies

  4. Exercise and the gastro-intestinal tract

    African Journals Online (AJOL)

    on perfonnance and me value of cardiovascular training in improving performance in aerobic sports is well recognised. The role of me gastro-intestinal tracr, bom as a limiting and sustaining facror in aerobic exercises, is less well appreciared. Gastro-intestinal symptoms. The spectrum of gastro-intestinal effecrs of exercise ...

  5. An evaluation of the importance of gastric acid secretion in the absorption of dietary calcium.

    OpenAIRE

    Bo-Linn, G W; Davis, G R; Buddrus, D J; Morawski, S G; Santa Ana, C; Fordtran, J S

    1984-01-01

    Since calcium solubility is a prerequisite to calcium absorption, and since solubility of calcium is highly pH-dependent, it has been generally assumed that gastric acid secretion and gastric acidity play an important role in the intestinal absorption of calcium from ingested food or calcium salts such as CaCO3. To evaluate this hypothesis, we developed a method wherein net gastrointestinal absorption of calcium can be measured after ingestion of a single meal. A large dose of cimetidine, whi...

  6. Mechanistic understanding of the effect of PPIs and acidic carbonated beverages on the oral absorption of itraconazole based on absorption modeling with appropriate in vitro data.

    Science.gov (United States)

    Fotaki, Nikoletta; Klein, Sandra

    2013-11-04

    Proton pump inhibitors (PPIs) are potent gastric acid suppressing agents and are among the most widely sold drugs in the world. However, even though these antisecretory agents are regarded as safe, they can alter the pharmacokinetics of coadministered drugs. Due to the suppression of gastric acid secretion, they can significantly alter the intragastric pH conditions and are thus likely to affect the bioavailability of coadministered drugs requiring an acidic gastric environment for dissolution and subsequent absorption. Among these drugs can be found itraconazole, a poorly soluble triazole-type antifungal compound. Based on observations reported in the literature, gastric pH alterations due to the coadministration of PPIs or acidic beverages can significantly decrease (PPI) or increase (e.g., Coca-Cola) the bioavailability of this compound. In the present work we estimated the fraction of itraconazole that can be absorbed (fabs) from Sporanox capsules or an itraconazole-HBenBCD complex formulation after oral administration with and without coadministration of a PPI or an acidic (carbonated) beverage. For this purpose, the sensitivity of the two formulations toward the impact of various gastric variations (pH, volume, and emptying rate) as they can result from such administration conditions was studied using solubility and dissolution experiments and a physiologically based absorption model. Simulating coadministration of the two formulations with a PPI resulted in a significant (∼ 10-fold) decrease in itraconazole fabs, indicating the pH to be essential for in vivo dissolution and subsequent absorption. The fabs of itraconazole after coadministration of an acidic beverage (Coca-Cola) was far lower than the fabs obtained for itraconazole alone and did not support the observations reported in the literature. These results clearly indicate that in contrast to PPIs, which seem to affect itraconazole bioavailability mainly via intragastric pH changes, coadministered

  7. Gastrointestinal Stromal Tumors: A Case Report

    Directory of Open Access Journals (Sweden)

    Palankezhe Sashidharan

    2014-03-01

    Full Text Available Advances in the identification of gastrointestinal stromal tumors, its molecular and immunohiostochemical basis, and its management have been a watershed in the treatment of gastrointestinal tumors. This paradigm shift occurred over the last two decades and gastrointestinal stromal tumors have now come to be understood as rare gastrointestinal tract tumors with predictable behavior and outcome, replacing the older terminologies like leiomyoma, schwannoma or leiomyosarcoma. This report presents a case of gastric gastrointestinal stromal tumor operated recently in a 47-year-old female patient and the outcome, as well as literature review of the pathological identification, sites of origin, and factors predicting its behavior, prognosis and treatment.

  8. Gastrointestinal function in the parasitized host

    International Nuclear Information System (INIS)

    Castro, G.A.

    1981-01-01

    Emphasis in this review is on (1) digestive-absorptive, secretory and smooth muscle functions altered by gastrointestinal (GI) parasites, (2) mechanisms by which parasites induce changes, and (3) the influence of parasite-induced alterations on the health of the host. Examples involving laboratory and domestic animals indicate that inflammation is an important factor in pathological alterations in epithelial and smooth muscle tissues throughout the alimentary canal. Observations on GI secretory activity reveal an influence of parasites on the host GI endocrine system. It is argued that assessments of the significance of parasite-induced changes on the host must be balanced with the adaptive potential and 'reserve capacity' of the GI system. In this regard host immunity should be considered a specific adaptation. Some tracer studies are mentioned marginally, such as the use of 14 C polyethylene glycol to estimate the direction of not fluid movement in the small intestine, and the use of 51 Cr to demonstrate the significantly faster intestinal transit in Trichinella spiralis infected animals

  9. Fractional Vector Calculus and Fractional Special Function

    OpenAIRE

    Li, Ming-Fan; Ren, Ji-Rong; Zhu, Tao

    2010-01-01

    Fractional vector calculus is discussed in the spherical coordinate framework. A variation of the Legendre equation and fractional Bessel equation are solved by series expansion and numerically. Finally, we generalize the hypergeometric functions.

  10. Radiopharmaceuticals and the gastrointestinal tract

    Energy Technology Data Exchange (ETDEWEB)

    Frier, M. [Radiopharmacy Unit, Dept. of Medical Physics, Queens Medical Centre, Univ. Hospital Nottingham (United Kingdom); Perkins, A.C. [Radiopharmacy Unit, Dept. of Medical Physics, Queens Medical Centre, Univ. Hospital Nottingham (United Kingdom)

    1994-11-01

    A review is presented of the design of radiolabelled test meals for the evaluation of gastrointestinal function, including oesophageal transit, gastro-oesophageal reflux, gastric emptying, enterogastric reflux and transit through the whole bowel. Descriptions of different systems are presented, together with validations of the procedures used. Published methods for assessment of oesophageal transit show a marked degree of consistency, whereas gastric emptying studies employ a wide range of both liquid and solid test meals. Recommendations are made concerning the optimal system for investigation of each part of the gastrointestinal tract, but whichever system is adopted, it is important to employ some validation procedures, and to establish normal ranges in the population under study. (orig.)

  11. Gastrointestinal hormones and their targets

    DEFF Research Database (Denmark)

    Rehfeld, Jens F.

    2014-01-01

    Gastrointestinal hormones are peptides released from endocrine cells and neurons in the digestive tract. More than 30 hormone genes are currently known to be expressed in the gastrointestinal tract, which makes the gut the largest hormone producing organ in the body. Modern biology makes...... it feasible to conceive the hormones under five headings: The structural homology groups a majority of the hormones into nine families, each of which is assumed to originate from one ancestral gene. The individual hormone gene often has multiple phenotypes due to alternative splicing, tandem organization......, or differentiated maturation of the prohormone. By a combination of these mechanisms, more than 100 different hormonally active peptides are released from the gut. Gut hormone genes are also widely expressed in cells outside the gut, some only in extraintestinal endocrine cells and neurons but others also in other...

  12. D-xylose absorption

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003606.htm D-xylose absorption To use the sharing features on this page, please enable JavaScript. D-xylose absorption is a laboratory test to determine ...

  13. Precision Medicine in Gastrointestinal Pathology.

    Science.gov (United States)

    Wang, David H; Park, Jason Y

    2016-05-01

    -Precision medicine is the promise of individualized therapy and management of patients based on their personal biology. There are now multiple global initiatives to perform whole-genome sequencing on millions of individuals. In the United States, an early program was the Million Veteran Program, and a more recent proposal in 2015 by the president of the United States is the Precision Medicine Initiative. To implement precision medicine in routine oncology care, genetic variants present in tumors need to be matched with effective clinical therapeutics. When we focus on the current state of precision medicine for gastrointestinal malignancies, it becomes apparent that there is a mixed history of success and failure. -To present the current state of precision medicine using gastrointestinal oncology as a model. We will present currently available targeted therapeutics, promising new findings in clinical genomic oncology, remaining quality issues in genomic testing, and emerging oncology clinical trial designs. -Review of the literature including clinical genomic studies on gastrointestinal malignancies, clinical oncology trials on therapeutics targeted to molecular alterations, and emerging clinical oncology study designs. -Translating our ability to sequence thousands of genes into meaningful improvements in patient survival will be the challenge for the next decade.

  14. Absorption and excretion tests

    International Nuclear Information System (INIS)

    Berberich, R.

    1988-01-01

    The absorption and excretion of radiopharmaceuticals is still of interest in diagnostic investigations of nuclear medicine. In this paper the most common methods of measuring absorption and excretion are described. The performance of the different tests and their standard values are discussed. More over the basic possibilities of measuring absorption and excretion including the needed measurement equipments are presented. (orig.) [de

  15. Assessment of the multi-mycotoxin-binding efficacy of a carbon/aluminosilicate-based product in an in vitro gastrointestinal model

    NARCIS (Netherlands)

    Avantaggiato, G.; Havenaar, R.; Visconti, A.

    2007-01-01

    A laboratory model, set to simulate the in vivo conditions of the porcine gastrointestinal tract, was used to study the small intestinal absorption of several mycotoxins and the effectiveness of Standard Q/FIS (a carbon/aluminosilicate-based product) in reducing mycotoxin absorption when added to

  16. Fractional separation of hydrocarbon vapours

    Energy Technology Data Exchange (ETDEWEB)

    1937-07-10

    A process is described for converting higher boiling hydrocarbons to lower boiling hydrocarbons by subjecting them at elevated temperatures to a conversion operation, then separating the higher and lower boiling fractions. The separation takes place while the reaction products are maintained in the vapor phase by contact with a mass of solid porous material which has little or no catalytic activity but does have a preferential absorption property for higher boiling hydrocarbons so that the lower boiling part of the reaction products pass through the separation zone while the heavier hydrocarbons are retained. The separation is accomplished without substantial loss of heat of these reaction products.

  17. Alteration of gastrointestinal transit time in the rat after bile duct cannulation surgery

    International Nuclear Information System (INIS)

    Ayres, P.H.; Medinsky, M.A.; Muggenburg, B.A.; Bond, J.A.

    1985-01-01

    Alteration of gastrointestinal (GI) transit time could affect the bioavailability of a toxicant if the toxicant is absorbed in the GI tract. The effect of surgery on GI transit time was investigated using radiographic imaging of barium during passage through the GI tract of the rat. Bile duct cannulation surgery delayed transit of barium to over 18 h, whereas in the normal animal, transit required approximately 6 h. GI transit time was only moderately affected by laparotomy after an 18-h postsurgery recovery period. These results suggest that the gastrointestinal absorption of orally administered toxicants could be affected by bile duct cannulation. 3 references, 1 figure, 1 table

  18. Abnormal gastrointestinal endocrine cells in patients with diabetes type 1: relationship to gastric emptying and myoelectrical activity.

    Science.gov (United States)

    El-Salhy, M; Sitohy, B

    2001-11-01

    Gastrointestinal symptoms in patients with diabetes are believed to be caused by gastrointestinal dysmotility and secretion/absorption disturbances, and the gut endocrine cells play an important part in regulating these two functions. Studies on animal models of human diabetes type I revealed abnormality in these cells, but it is unknown whether abnormality also occurs in patients with diabetes. Eleven patients with long duration of diabetes type I and organ complications, as well as gastrointestinal symptoms, were studied. Endocrine cells in different segments of the gastrointestinal tract were detected by immunocytochemistry and quantified by computerized image analysis. Gastric emptying was measured by scintigraphy and gastric myoelectric activity was determined by electrogastrography. An abnormal density of gastrointestinal endocrine cells was found in patients with diabetes. This abnormality occurred in all segments of the upper and lower gastrointestinal tract investigated, and included most of the endocrine cell types. The patients showed delayed gastric emptying, which correlated closely with the acute glucose level, but did not correlate with HbA1c. Gastric emptying also correlated closely with the density of duodenal serotonin and secretin cells. The patients exhibited bradygastrias and tachygastrias. These dysrhythmias, however, did not differ significantly from controls. The endocrine cells are the anatomical units responsible for the production of gut hormones, and the change in their density would reflect a change in the capacity of producing these hormones. The abnormality in density of the gastrointestinal endocrine cells may contribute to the development of gastrointestinal dysmotility and the symptoms encountered in patients with diabetes.

  19. Absorption of acoustic waves by sunspots. II - Resonance absorption in axisymmetric fibril models

    Science.gov (United States)

    Rosenthal, C. S.

    1992-01-01

    Analytical calculations of acoustic waves scattered by sunspots which concentrate on the absorption at the magnetohydrodynamic Alfven resonance are extended to the case of a flux-tube embedded in a uniform atmosphere. The model is based on a flux-tubes of varying radius that are highly structured, translationally invariant, and axisymmetric. The absorbed fractional energy is determined for different flux-densities and subphotospheric locations with attention given to the effects of twist. When the flux is highly concentrated into annuli efficient absorption is possible even when the mean magnetic flux density is low. The model demonstrates low absorption at low azimuthal orders even in the presence of twist which generally increases the range of wave numbers over which efficient absorption can occur. Resonance absorption is concluded to be an efficient mechanism in monolithic sunspots, fibril sunspots, and plage fields.

  20. Fractional quantum mechanics

    CERN Document Server

    Laskin, Nick

    2018-01-01

    Fractional quantum mechanics is a recently emerged and rapidly developing field of quantum physics. This is the first monograph on fundamentals and physical applications of fractional quantum mechanics, written by its founder. The fractional Schrödinger equation and the fractional path integral are new fundamental physical concepts introduced and elaborated in the book. The fractional Schrödinger equation is a manifestation of fractional quantum mechanics. The fractional path integral is a new mathematical tool based on integration over Lévy flights. The fractional path integral method enhances the well-known Feynman path integral framework. Related topics covered in the text include time fractional quantum mechanics, fractional statistical mechanics, fractional classical mechanics and the α-stable Lévy random process. The book is well-suited for theorists, pure and applied mathematicians, solid-state physicists, chemists, and others working with the Schrödinger equation, the path integral technique...

  1. Acetaminophen (paracetamol) oral absorption and clinical influences.

    Science.gov (United States)

    Raffa, Robert B; Pergolizzi, Joseph V; Taylor, Robert; Decker, John F; Patrick, Jeffrey T

    2014-09-01

    Acetaminophen (paracetamol) is a widely used nonopioid, non-NSAID analgesic that is effective against a variety of pain types, but the consequences of overdose can be severe. Because acetaminophen is so widely available as a single agent and is increasingly being formulated in fixed-ratio combination analgesic products for the potential additive or synergistic analgesic effect and/or reduced adverse effects, accidental cumulative overdose is an emergent concern. This has rekindled interest in the sites, processes, and pharmacokinetics of acetaminophen oral absorption and the clinical factors that can influence these. The absorption of oral acetaminophen occurs primarily along the small intestine by passive diffusion. Therefore, the rate-limiting step is the rate of gastric emptying into the intestines. Several clinical factors can affect absorption per se or the rate of gastric emptying, such as diet, concomitant medication, surgery, pregnancy, and others. Although acetaminophen does not have the abuse potential of opioids or the gastrointestinal bleeding or organ adverse effects of NSAIDs, excess amounts can produce serious hepatic injury. Thus, an understanding of the sites and features of acetaminophen absorption--and how they might be influenced by factors encountered in clinical practice--is important for pain management using this agent. It can also provide insight for design of formulations that would be less susceptible to clinical variables. © 2013 World Institute of Pain.

  2. Fractional vector calculus and fractional Maxwell's equations

    International Nuclear Information System (INIS)

    Tarasov, Vasily E.

    2008-01-01

    The theory of derivatives and integrals of non-integer order goes back to Leibniz, Liouville, Grunwald, Letnikov and Riemann. The history of fractional vector calculus (FVC) has only 10 years. The main approaches to formulate a FVC, which are used in the physics during the past few years, will be briefly described in this paper. We solve some problems of consistent formulations of FVC by using a fractional generalization of the Fundamental Theorem of Calculus. We define the differential and integral vector operations. The fractional Green's, Stokes' and Gauss's theorems are formulated. The proofs of these theorems are realized for simplest regions. A fractional generalization of exterior differential calculus of differential forms is discussed. Fractional nonlocal Maxwell's equations and the corresponding fractional wave equations are considered

  3. Upper gastrointestinal bleeding in patients with CKD.

    Science.gov (United States)

    Liang, Chih-Chia; Wang, Su-Ming; Kuo, Huey-Liang; Chang, Chiz-Tzung; Liu, Jiung-Hsiun; Lin, Hsin-Hung; Wang, I-Kuan; Yang, Ya-Fei; Lu, Yueh-Ju; Chou, Che-Yi; Huang, Chiu-Ching

    2014-08-07

    Patients with CKD receiving maintenance dialysis are at risk for upper gastrointestinal bleeding. However, the risk of upper gastrointestinal bleeding in patients with early CKD who are not receiving dialysis is unknown. The hypothesis was that their risk of upper gastrointestinal bleeding is negatively linked to renal function. To test this hypothesis, the association between eGFR and risk of upper gastrointestinal bleeding in patients with stages 3-5 CKD who were not receiving dialysis was analyzed. Patients with stages 3-5 CKD in the CKD program from 2003 to 2009 were enrolled and prospectively followed until December of 2012 to monitor the development of upper gastrointestinal bleeding. The risk of upper gastrointestinal bleeding was analyzed using competing-risks regression with time-varying covariates. In total, 2968 patients with stages 3-5 CKD who were not receiving dialysis were followed for a median of 1.9 years. The incidence of upper gastrointestinal bleeding per 100 patient-years was 3.7 (95% confidence interval, 3.5 to 3.9) in patients with stage 3 CKD, 5.0 (95% confidence interval, 4.8 to 5.3) in patients with stage 4 CKD, and 13.9 (95% confidence interval, 13.1 to 14.8) in patients with stage 5 CKD. Higher eGFR was associated with a lower risk of upper gastrointestinal bleeding (P=0.03), with a subdistribution hazard ratio of 0.93 (95% confidence interval, 0.87 to 0.99) for every 5 ml/min per 1.73 m(2) higher eGFR. A history of upper gastrointestinal bleeding (Pupper gastrointestinal bleeding risk. In patients with CKD who are not receiving dialysis, lower renal function is associated with higher risk for upper gastrointestinal bleeding. The risk is higher in patients with previous upper gastrointestinal bleeding history and low serum albumin. Copyright © 2014 by the American Society of Nephrology.

  4. Gastrointestinal helminths in migratory Camel

    Directory of Open Access Journals (Sweden)

    S G Rewatkar

    Full Text Available Survey of gastrointestinal helminth parasites in camel migrated from U.P., M.P., and Rajasthan at Nagpur region was carried out in early summer, 2008. Total 28 samples (12 males and 16 females were collected from different places of Nagpur region. They revealed parasites as Trichuris sp.(50%, Strongyloides sp.(32.14%, Trichostrongylus sp.(10.71%, Nematodirus sp.(10.71%, Haemonchus sp.(14.28%, Eurytrema sp.(21.42% ,Eimeria sp.(25%, Entamoeba sp.(17.85% and Balantidium sp.(7.14%.All were found positive for mixed helminthic infection. [Vet World 2009; 2(7.000: 258-258

  5. Gastrointestinal obstruction in penguin chicks.

    Science.gov (United States)

    Perpiñán, David; Curro, Thomas G

    2009-12-01

    A 7-day-old gentoo penguin (Pygoscelis papua) was found dead and postmortem examination revealed impaction of the ventriculus with feathers. A review of mortality in gentoo penguin chicks from 1997 to 2007 at that institution revealed another case of feather impaction of the ventriculus in a 4-week-old chick, a sibling of the previous chick. A third case of gastrointestinal impaction occurred in a 24-day-old king penguin (Aptenodytes patagonicus) with omphallitis and enteritis. In this chick, a fibrin mat produced a complete obstruction of the intestine at the level of Meckel's diverticulum.

  6. Fraccionando la microbiota gastrointestinal humana

    OpenAIRE

    Peris Bondia, Francisco

    2012-01-01

    La microbiota gastrointestinal humana es una de las comunidades microbianas más diversa y compleja que se puede encontrar en la naturaleza. Las nuevas tecnologías de secuenciación permiten obtener una amplia visión de la diversidad microbiana, lo que ha revelado una gran cantidad de bacterias no cultivables. A pesar del potencial de estas tecnologías de alto rendimiento la metagenómica no muestra la imagen completa. La citometría de flujo es una metodología que permite describir y/o separa...

  7. Fractional statistics and fractional quantized Hall effect

    International Nuclear Information System (INIS)

    Tao, R.; Wu, Y.S.

    1985-01-01

    The authors suggest that the origin of the odd-denominator rule observed in the fractional quantized Hall effect (FQHE) may lie in fractional statistics which govern quasiparticles in FQHE. A theorem concerning statistics of clusters of quasiparticles implies that fractional statistics do not allow coexistence of a large number of quasiparticles at fillings with an even denominator. Thus, no Hall plateau can be formed at these fillings, regardless of the presence of an energy gap. 15 references

  8. [Study on lead absorption in pumpkin by atomic absorption spectrophotometry].

    Science.gov (United States)

    Li, Zhen-Xia; Sun, Yong-Dong; Chen, Bi-Hua; Li, Xin-Zheng

    2008-07-01

    A study was carried out on the characteristic of lead absorption in pumpkin via atomic absorption spectrophotometer. The results showed that lead absorption amount in pumpkin increased with time, but the absorption rate decreased with time; And the lead absorption amount reached the peak in pH 7. Lead and cadmium have similar characteristic of absorption in pumpkin.

  9. Initialized Fractional Calculus

    Science.gov (United States)

    Lorenzo, Carl F.; Hartley, Tom T.

    2000-01-01

    This paper demonstrates the need for a nonconstant initialization for the fractional calculus and establishes a basic definition set for the initialized fractional differintegral. This definition set allows the formalization of an initialized fractional calculus. Two basis calculi are considered; the Riemann-Liouville and the Grunwald fractional calculi. Two forms of initialization, terminal and side are developed.

  10. A retrospective study of the effects of pelvic irradiation for carcinoma of the cervix on gastrointestinal function

    International Nuclear Information System (INIS)

    Yeoh, E.; Ahmad, A.; Horowitz, M.; Russo, A.; Muecke, T.; Chatterton, B.; Robb, T.

    1993-01-01

    The purpose of the study was to evaluate the prevalence of disordered gastrointestinal function following therapeutic irradiation. Gastrointestinal function was evaluated in 30 randomly selected patients who had received pelvic irradiation for treatment of carcinoma of the cervix between 1 and 6 years previously. Each patient underwent evaluations of (a) gastrointestinal symptoms (b) absorption of bile acid, vitamin B12, lactose and fat (c) gastrointestinal transit: gastric emptying, small intestinal transit and whole gut transit and (d) intestinal permeability. Results were compared with those obtained in 18 normal volunteers. Stool frequency was above the control range in five patients and had increased (p < 0.001) since radiotherapy treatment. Bile acid (p<0.001) vitamin B12(p<0.01) and lactose (p<0.01) absorption were less in the patients when compared with the control subjects. Bile acid adsorption was below the control range in 14 of the 30 patients. Dietary calcium intake was lower (p<0.05) in those patients with lactose malabsorption. Gastric emptying (p<0.01) and small intestinal transit (p<0.01) were more rapid in the patients. Both small intestinal (r=-0.39, p<0.05) and whole gut (r=-0.45) transit were inversely related to stool frequency. Either bowel frequency, bile acid adsorption, vitamin B12 absorption was outside the control range in 19 of the 30 patients. Abnormal gastrointestinal function is essentially an inevitable long-term sequel of pelvic irradiation. 41 refs., 4 figs., 3 tabs

  11. Tempered fractional calculus

    Energy Technology Data Exchange (ETDEWEB)

    Sabzikar, Farzad, E-mail: sabzika2@stt.msu.edu [Department of Statistics and Probability, Michigan State University, East Lansing, MI 48823 (United States); Meerschaert, Mark M., E-mail: mcubed@stt.msu.edu [Department of Statistics and Probability, Michigan State University, East Lansing, MI 48823 (United States); Chen, Jinghua, E-mail: cjhdzdz@163.com [School of Sciences, Jimei University, Xiamen, Fujian, 361021 (China)

    2015-07-15

    Fractional derivatives and integrals are convolutions with a power law. Multiplying by an exponential factor leads to tempered fractional derivatives and integrals. Tempered fractional diffusion equations, where the usual second derivative in space is replaced by a tempered fractional derivative, govern the limits of random walk models with an exponentially tempered power law jump distribution. The limiting tempered stable probability densities exhibit semi-heavy tails, which are commonly observed in finance. Tempered power law waiting times lead to tempered fractional time derivatives, which have proven useful in geophysics. The tempered fractional derivative or integral of a Brownian motion, called a tempered fractional Brownian motion, can exhibit semi-long range dependence. The increments of this process, called tempered fractional Gaussian noise, provide a useful new stochastic model for wind speed data. A tempered fractional difference forms the basis for numerical methods to solve tempered fractional diffusion equations, and it also provides a useful new correlation model in time series.

  12. Tempered fractional calculus

    Science.gov (United States)

    Sabzikar, Farzad; Meerschaert, Mark M.; Chen, Jinghua

    2015-07-01

    Fractional derivatives and integrals are convolutions with a power law. Multiplying by an exponential factor leads to tempered fractional derivatives and integrals. Tempered fractional diffusion equations, where the usual second derivative in space is replaced by a tempered fractional derivative, govern the limits of random walk models with an exponentially tempered power law jump distribution. The limiting tempered stable probability densities exhibit semi-heavy tails, which are commonly observed in finance. Tempered power law waiting times lead to tempered fractional time derivatives, which have proven useful in geophysics. The tempered fractional derivative or integral of a Brownian motion, called a tempered fractional Brownian motion, can exhibit semi-long range dependence. The increments of this process, called tempered fractional Gaussian noise, provide a useful new stochastic model for wind speed data. A tempered fractional difference forms the basis for numerical methods to solve tempered fractional diffusion equations, and it also provides a useful new correlation model in time series.

  13. Tempered fractional calculus

    International Nuclear Information System (INIS)

    Sabzikar, Farzad; Meerschaert, Mark M.; Chen, Jinghua

    2015-01-01

    Fractional derivatives and integrals are convolutions with a power law. Multiplying by an exponential factor leads to tempered fractional derivatives and integrals. Tempered fractional diffusion equations, where the usual second derivative in space is replaced by a tempered fractional derivative, govern the limits of random walk models with an exponentially tempered power law jump distribution. The limiting tempered stable probability densities exhibit semi-heavy tails, which are commonly observed in finance. Tempered power law waiting times lead to tempered fractional time derivatives, which have proven useful in geophysics. The tempered fractional derivative or integral of a Brownian motion, called a tempered fractional Brownian motion, can exhibit semi-long range dependence. The increments of this process, called tempered fractional Gaussian noise, provide a useful new stochastic model for wind speed data. A tempered fractional difference forms the basis for numerical methods to solve tempered fractional diffusion equations, and it also provides a useful new correlation model in time series

  14. Concurrent duodenal manometric and impedance recording to evaluate the effects of hyoscine on motility and flow events, glucose absorption, and incretin release

    NARCIS (Netherlands)

    Chaikomin, Reawika; Wu, Keng Liang; Doran, Selena; Jones, Karen L.; Smout, Andre J. P. M.; Renooij, Willem; Holloway, Richard H.; Meyer, James H.; Horowitz, Michael; Rayner, Christopher K.

    2007-01-01

    Upper gastrointestinal motor function and incretin hormone secretion are major determinants of postprandial glycemia and insulinemia. However, the impact of small intestinal flow events on glucose absorption and incretin release is poorly defined. Intraluminal impedance monitoring is a novel

  15. Absorption heat pumps

    International Nuclear Information System (INIS)

    Formigoni, C.

    1998-01-01

    A brief description of the difference between a compression and an absorption heat pump is made, and the reasons why absorption systems have spread lately are given. Studies and projects recently started in the field of absorption heat pumps, as well as criteria usually followed in project development are described. An outline (performance targets, basic components) of a project on a water/air absorption heat pump, running on natural gas or LPG, is given. The project was developed by the Robur Group as an evolution of a water absorption refrigerator operating with a water/ammonia solution, which has been on the market for a long time and recently innovated. Finally, a list of the main energy and cost advantages deriving from the use of absorption heat pumps is made [it

  16. Gastrointestinal Transit Time, Glucose Homeostasis and Metabolic Health: Modulation by Dietary Fibers.

    Science.gov (United States)

    Müller, Mattea; Canfora, Emanuel E; Blaak, Ellen E

    2018-02-28

    Gastrointestinal transit time may be an important determinant of glucose homeostasis and metabolic health through effects on nutrient absorption and microbial composition, among other mechanisms. Modulation of gastrointestinal transit may be one of the mechanisms underlying the beneficial health effects of dietary fibers. These effects include improved glucose homeostasis and a reduced risk of developing metabolic diseases such as obesity and type 2 diabetes mellitus. In this review, we first discuss the regulation of gastric emptying rate, small intestinal transit and colonic transit as well as their relation to glucose homeostasis and metabolic health. Subsequently, we briefly address the reported health effects of different dietary fibers and discuss to what extent the fiber-induced health benefits may be mediated through modulation of gastrointestinal transit.

  17. Ghrelin and gastrointestinal stromal tumors.

    Science.gov (United States)

    Zhu, Chang-Zhen; Liu, Dong; Kang, Wei-Ming; Yu, Jian-Chun; Ma, Zhi-Qiang; Ye, Xin; Li, Kang

    2017-03-14

    Ghrelin, as a kind of multifunctional protein polypeptide, is mainly produced in the fundus of the stomach and can promote occurrence and development of many tumors, including gastrointestinal tumors, which has been proved by the relevant researches. Most gastrointestinal stromal tumors (GISTs, about 80%), as the most common mesenchymal tumor, also develop in the fundus. Scientific research has confirmed that ghrelin, its receptors and mRNA respectively can be found in GISTs, which demonstrated the existence of a ghrelin autocrine/paracrine loop in GIST tissues. However, no reports to date have specified the mechanism whether ghrelin can promote the occurrence and development of GISTs. Studies of pulmonary artery endothelial cells in a low-oxygen environment and cardiac muscle cells in an ischemic environment have shown that ghrelin can activate the phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway. Moreover, some studies of GISTs have confirmed that activation of the PI3K/AKT/mTOR pathway can indeed promote the growth and progression of GISTs. Whether ghrelin is involved in the development or progression of GISTs through certain pathways remains unknown. Can we find a new target for the treatment of GISTs? This review explores and summaries the relationship among ghrelin, the PI3K/AKT/mTOR pathway and the development of GISTs.

  18. Does Hypothyroidism Affect Gastrointestinal Motility?

    Directory of Open Access Journals (Sweden)

    Olga Yaylali

    2009-01-01

    Full Text Available Background. Gastrointestinal motility and serum thyroid hormone levels are closely related. Our aim was to analyze whether there is a disorder in esophagogastric motor functions as a result of hypothyroidism. Materials and Methods. The study group included 30 females (mean age ± SE 45.17 ± 2.07 years with primary hypothyroidism and 10 healthy females (mean age ± SE 39.40 ± 3.95 years. All cases underwent esophagogastric endoscopy and scintigraphy. For esophageal scintigraphy, dynamic imaging of esophagus motility protocol, and for gastric emptying scintigraphy, anterior static gastric images were acquired. Results. The mean esophageal transit time (52.56 ± 4.07 sec for patients; 24.30 ± 5.88 sec for controls; P=.02 and gastric emptying time (49.06 ± 4.29 min for the hypothyroid group; 30.4 ± 4.74 min for the control group; P=.01 were markedly increased in cases of hypothyroidism. Conclusion. Hypothyroidism prominently reduces esophageal and gastric motor activity and can cause gastrointestinal dysfunction.

  19. Radiological diagnosis of gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Neufang, K.F.R.; Gross-Fengels, W.; Lorenz, R.

    1990-01-01

    In the diagnosis of acute gastrointestinal bleeding, endoscopy holds the first place today. Radiological investigations are indispensable whenever endoscopy cannot precisely localise the bleeding site, whenever a tumour is present or suspected, in all cases of lower gastrointestinal bleeding, and in haemobilia. A tailored radiological approach is recommended. The radiological basis programme should be at least a complete abdominal ultrasound study and plain abdominal radiograms. CT and ERCP scans may become necessary in selected cases. As a rule, angiographical localisation of the bleeding site will be successful only in the acute stage; selective visceral arteriograms have to be obtained, which may be executed in the digital subtraction technique in patients who are cooperating and clinically stable. Angiodysplasias and aneurysms, however, may be demonstrated angiographically in the interval as well. Upper and/or lower G.I. tract studies with barium or water-soluble contrast media may be indicated in the interval in order to demonstrate tumours, metastatic lesions, diverticula and gut malformations. (orig.) [de

  20. Higher fractions theory of fractional hall effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.; Popov, V.N.

    1985-07-01

    A theory of fractional quantum Hall effect is generalized to higher fractions. N-particle model interaction is used and the gap is expressed through n-particles wave function. The excitation spectrum in general and the mean field critical behaviour are determined. The Hall conductivity is calculated from first principles. (author)

  1. Inactivation of Bacillus cereus vegetative cells by gastric acid and bile during in vitro gastrointestinal transit

    Directory of Open Access Journals (Sweden)

    Ceuppens Siele

    2012-10-01

    Full Text Available Abstract Background The foodborne pathogen Bacillus cereus can cause diarrhoeal food poisoning by production of enterotoxins in the small intestine. The prerequisite for diarrhoeal disease is thus survival during gastrointestinal passage. Methods Vegetative cells of 3 different B. cereus strains were cultivated in a real composite food matrix, lasagne verde, and their survival during subsequent simulation of gastrointestinal passage was assessed using in vitro experiments simulating transit through the human upper gastrointestinal tract (from mouth to small intestine. Results No survival of vegetative cells was observed, despite the high inoculum levels of 7.0 to 8.0 log CFU/g and the presence of various potentially protective food components. Significant fractions (approx. 10% of the consumed inoculum of B. cereus vegetative cells survived gastric passage, but they were subsequently inactivated by bile exposure in weakly acidic intestinal medium (pH 5.0. In contrast, the low numbers of spores present (up to 4.0 log spores/g showed excellent survival and remained viable spores throughout the gastrointestinal passage simulation. Conclusion Vegetative cells are inactivated by gastric acid and bile during gastrointestinal passage, while spores are resistant and survive. Therefore, the physiological form (vegetative cells or spores of the B. cereus consumed determines the subsequent gastrointestinal survival and thus the infective dose, which is expected to be much lower for spores than vegetative cells. No significant differences in gastrointestinal survival ability was found among the different strains. However, considerable strain variability was observed in sporulation tendency during growth in laboratory medium and food, which has important implications for the gastrointestinal survival potential of the different B. cereus strains.

  2. Biokinetic modelling development and analysis of arsenic dissolution into the gastrointestinal tract using SAAM II

    Science.gov (United States)

    Perama, Yasmin Mohd Idris; Siong, Khoo Kok

    2018-04-01

    A mathematical model comprising 8 compartments were designed to describe the kinetic dissolution of arsenic (As) from water leach purification (WLP) waste samples ingested into the gastrointestinal system. A totally reengineered software system named Simulation, Analysis and Modelling II (SAAM II) was employed to aid in the experimental design and data analysis. As a powerful tool that creates, simulate and analyze data accurately and rapidly, SAAM II computationally creates a system of ordinary differential equations according to the specified compartmental model structure and simulates the solutions based upon the parameter and model inputs provided. The experimental design of in vitro DIN approach was applied to create an artificial gastric and gastrointestinal fluids. These synthetic fluids assay were produced to determine the concentrations of As ingested into the gastrointestinal tract. The model outputs were created based upon the experimental inputs and the recommended fractional transfer rates parameter. As a result, the measured and predicted As concentrations in gastric fluids were much similar against the time of study. In contrast, the concentrations of As in the gastrointestinal fluids were only similar during the first hour and eventually started decreasing until the fifth hours of study between the measured and predicted values. This is due to the loss of As through the fractional transfer rates of q2 compartment to corresponding compartments of q3 and q5 which are involved with excretion and distribution to the whole body, respectively. The model outputs obtained after best fit to the data were influenced significantly by the fractional transfer rates between each compartment. Therefore, a series of compartmental model created with the association of fractional transfer rates parameter with the aid of SAAM II provides better estimation that simulate the kinetic behavior of As ingested into the gastrointestinal system.

  3. Antimutagenic activity of green tea and black tea extracts studied in a dynamic in vitro gastrointestinal model

    NARCIS (Netherlands)

    Krul, C.A.M.; Luiten-Schuite, A.; Tenfelde, A.; Ommen, B. van; Verhagen, H.; Havenaar, R.

    2001-01-01

    An in vitro gastrointestinal model, which simulates the conditions in the human digestive tract, was used to determine potential antimutagenic activity of extracts of black tea and green tea. In this paper, results are presented on the availability for absorption of potential antimutagenic compounds

  4. The absorption factor of crystalline silicon PV cells: a numerical and experimental study

    NARCIS (Netherlands)

    Santbergen, R.; Zolingen, van R.J.C.

    2008-01-01

    The absorption factor of a PV cell is defined as the fraction of incident solar irradiance that is absorbed by the cell. This absorption factor is one of the major parameters determining the cell temperature under operational conditions. Experimentally the absorption factor can be derived from

  5. Computed tomography of the gastrointestinal tract

    International Nuclear Information System (INIS)

    Fishman, E.K.; Jones, B.

    1988-01-01

    This book contains 11 chapters and five case studies. Some of the chapter titles are: CT of the Stomach; CT and Other Inflammatory Bowel Disease; Evaluation of Crohn's Disease; Periotoneal Metastasis; CT and MRI Correlation of the Gastrointestinal Tract; CT of Acute Gastrointestinal Abnormlities; and CT of Colorectal Cancer

  6. Possible Waardenburg syndrome with gastrointestinal anomalies.

    OpenAIRE

    Nutman, J; Steinherz, R; Sivan, Y; Goodman, R M

    1986-01-01

    We describe a patient with possible Waardenburg syndrome associated with anal atresia and oesophageal atresia with tracheooesophageal fistula. Three other published cases with atretic gastrointestinal anomalies associated with the Waardenburg syndrome are reviewed. We conclude that the association between atretic lesions of the gastrointestinal tract and the Waardenburg syndrome may be a significant one.

  7. Possible Waardenburg syndrome with gastrointestinal anomalies.

    Science.gov (United States)

    Nutman, J; Steinherz, R; Sivan, Y; Goodman, R M

    1986-01-01

    We describe a patient with possible Waardenburg syndrome associated with anal atresia and oesophageal atresia with tracheooesophageal fistula. Three other published cases with atretic gastrointestinal anomalies associated with the Waardenburg syndrome are reviewed. We conclude that the association between atretic lesions of the gastrointestinal tract and the Waardenburg syndrome may be a significant one. Images PMID:3712396

  8. Unsedated Flexible Upper Gastrointestinal Endoscopy: Need for ...

    African Journals Online (AJOL)

    Background: To determine the incidence of oxygen desaturation and whether routine oxygen monitoring is necessary during unsedated diagnostic flexible upper gastrointestinal endoscopy. Methods: A prospective study involving 54 consecutive in and out patients who had diagnostic upper gastrointestinal endoscopy at ...

  9. Peptide Hormones in the Gastrointestinal Tract

    DEFF Research Database (Denmark)

    Rehfeld, Jens F.

    2015-01-01

    Gastrointestinal hormones are peptides released from endocrine cells and neurons in the digestive tract. More than 30 hormone genes are currently known to be expressed in the gastrointestinal tract, which makes the gut the largest hormone-producing organ in the body. Modern biology makes it feasi...

  10. Mammalian gastrointestinal parasites in rainforest remnants

    Indian Academy of Sciences (India)

    Here, we studied the gastrointestinal parasites of nonhuman mammalian hosts living in 10 rainforest patches of the Anamalai Tiger Reserve, India. We examined 349 faecal samples of 17 mammalian species and successfully identified 24 gastroin-testinal parasite taxa including 1 protozoan, 2 trematode, 3 cestode and 18 ...

  11. Antidepressants and gastrointestinal symptoms in the general Dutch adult population

    NARCIS (Netherlands)

    Schurink, B.; Tielemans, M.M.; Aaldering, B.R.; Eikendal, T.; Jaspers Focks, J.; Laheij, R.J.F.; Jansen, J.B.M.J.; Rossum, L.G.M. van; Oijen, M.G.H. van

    2014-01-01

    BACKGROUND: Gastrointestinal symptoms are frequently reported adverse effects of antidepressants, but antidepressants are also a treatment modality in functional gastrointestinal disorders. We aimed to assess the association between antidepressant use and gastrointestinal symptoms in the general

  12. Solar absorption surface panel

    Science.gov (United States)

    Santala, Teuvo J.

    1978-01-01

    A composite metal of aluminum and nickel is used to form an economical solar absorption surface for a collector plate wherein an intermetallic compound of the aluminum and nickel provides a surface morphology with high absorptance and relatively low infrared emittance along with good durability.

  13. Nutrition and magnesium absorption

    NARCIS (Netherlands)

    Brink, E.J.

    1992-01-01

    The influence of various nutrients present in dairy products and soybean-based products on absorption of magnesium has been investigated. The studies demonstrate that soybean protein versus casein lowers apparent magnesium absorption in rats through its phytate component. However, true

  14. Zeeman atomic absorption spectroscopy

    International Nuclear Information System (INIS)

    Loos-Vollebregt, M.T.C. de.

    1980-01-01

    A new method of background correction in atomic absorption spectroscopy has recently been introduced, based on the Zeeman splitting of spectral lines in a magnetic field. A theoretical analysis of the background correction capability observed in such instruments is presented. A Zeeman atomic absorption spectrometer utilizing a 50 Hz sine wave modulated magnetic field is described. (Auth.)

  15. HIV-Associated Gastrointestinal Cancer.

    Science.gov (United States)

    Jensen, Björn E-O; Oette, Mark; Haes, Johannes; Häussinger, Dieter

    2017-01-01

    People living nowadays with HIV and AIDS may be treated effectively regarding virus replication and immunology. However, non-AIDS-defining cancer is of growing relevance due to high incidence and unfavorable outcome. The aim of this review is to summarize current knowledge on gastrointestinal (GI) carcinoma. Although literature on GI cancer is rare, an increased incidence of esophageal, gastric, pancreatic, hepatocellular, and colorectal carcinoma has been demonstrated. However, there are only few reports on therapy strategies and outcome, so that, despite increased occurrence of many GI carcinomas, only little is known about individualized treatment options and outcome in HIV-positive patients. More efforts have to be undertaken to close this gap. © 2017 S. Karger GmbH, Freiburg.

  16. Malignant tumors of gastrointestinal tract

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    International histological classification and classification according to TNM systems, domestic clinical classification according to stages of carcinoma of stomach, large intestine and rectum are presented. Diagnosis of tumoral processes of the given localizations should be based on complex application of diagnostic methods: clinical, ultrasonic, radiological and others. Surgical method and variants of surgical method with preoperative radiotherapy play a leading role in treatment of mentioned tumors. Combined method of treatment-surgical intervention with postoperation intravenous injection of colloid 198 Au - is applied for preventing propagation of stomach cancer metastases. Advisability of combining operations with radiological and antitumoral medicamentous therapy is shown. Reliable results of treatment of malignant tumors of gastrointestinal tract are presented

  17. Measurement of void fractions by nuclear techniques; Medicion de fracciones de vacio por tecnicas nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez G, A.; Vazquez G, J.; Diaz H, C.; Salinas R, G.A. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    In this work it is done a general analysis of those techniques used to determine void fractions and it is chosen a nuclear technique to be used in the heat transfer circuit of the Physics Department of the Basic Sciences Management. The used methods for the determination of void fractions are: radioactive absorption, acoustic techniques, average velocity measurement, electromagnetic flow measurement, optical methods, oscillating absorption, nuclear magnetic resonance, relation between pressure and flow oscillation, infrared absorption methods, sound neutron analysis. For the case of this work it will be treated about the radioactive absorption method which is based in the gamma rays absorption. (Author)

  18. Asphalt chemical fractionation

    International Nuclear Information System (INIS)

    Obando P, Klever N.

    1998-01-01

    Asphalt fractionation were carried out in the Esmeraldas Oil Refinery using n-pentane, SiO 2 and different mixture of benzene- methane. The fractions obtained were analyzed by Fourier's Transformed Infrared Spectrophotometry (FTIR)

  19. Reporting systems in gastrointestinal endoscopy: Requirements and standards facilitating quality improvement: European Society of Gastrointestinal Endoscopy position statement

    NARCIS (Netherlands)

    Bretthauer, Michael; Aabakken, Lars; Dekker, Evelien; Kaminski, Michal F.; Rösch, Thomas; Hultcrantz, Rolf; Suchanek, Stepan; Jover, Rodrigo; Kuipers, Ernst J.; Bisschops, Raf; Spada, Cristiano; Valori, Roland; Domagk, Dirk; Rees, Colin; Rutter, Matthew D.

    2016-01-01

    To develop standards for high quality of gastrointestinal endoscopy, the European Society of Gastrointestinal Endoscopy (ESGE) has established the ESGE Quality Improvement Committee. A prerequisite for quality assurance and improvement for all gastrointestinal endoscopy procedures is

  20. Smarandache Continued Fractions

    OpenAIRE

    Ibstedt, H.

    2001-01-01

    The theory of general continued fractions is developed to the extent required in order to calculate Smarandache continued fractions to a given number of decimal places. Proof is given for the fact that Smarandache general continued fractions built with positive integer Smarandache sequences baving only a finite number of terms equal to 1 is convergent. A few numerical results are given.

  1. Quasar Absorption Studies

    Science.gov (United States)

    Mushotzky, Richard (Technical Monitor); Elvis, Martin

    2004-01-01

    The aim of the proposal is to investigate the absorption properties of a sample of inter-mediate redshift quasars. The main goals of the project are: Measure the redshift and the column density of the X-ray absorbers; test the correlation between absorption and redshift suggested by ROSAT and ASCA data; constrain the absorber ionization status and metallicity; constrain the absorber dust content and composition through the comparison between the amount of X-ray absorption and optical dust extinction. Unanticipated low energy cut-offs where discovered in ROSAT spectra of quasars and confirmed by ASCA, BeppoSAX and Chandra. In most cases it was not possible to constrain adequately the redshift of the absorber from the X-ray data alone. Two possibilities remain open: a) absorption at the quasar redshift; and b) intervening absorption. The evidences in favour of intrinsic absorption are all indirect. Sensitive XMM observations can discriminate between these different scenarios. If the absorption is at the quasar redshift we can study whether the quasar environment evolves with the Cosmic time.

  2. Nasal Absorption of Macromolecules from Powder Formulations and Effects of Sodium Carboxymethyl Cellulose on Their Absorption.

    Directory of Open Access Journals (Sweden)

    Akiko Tanaka

    Full Text Available The nasal absorption of macromolecules from powder formulations and the effect of sodium carboxymethyl cellulose (CMC-Na as a pharmaceutical excipient on their absorption were studied. Model macromolecules were fluorescein isothiocyanate-labeled dextran (average molecular weight of 4.4kDa, FD4 and insulin. The plasma concentration of FD4 after application of the powder containing 50% starch (control was higher than that after application of the solution, and the absorption from 50% starch powder was enhanced by the substitution of starch with CMC-Na. The fractional absorption of FD4 after administration of the CMC-Na powder formulation was 30% and 40% higher than that after administration from the solution and the starch powder, respectively. The nasal absorption of insulin from the powder and the effect of CMC-Na were similar with those of FD4. The effective absorption of FD4 and insulin after application of powder with CMC-Na could be due to the increase in the nasal residence of FD4 and insulin. No damage in the nasal mucosa or dysfunction of the mucociliary clearance was observed after application of the drug powder and CMC-Na. The present findings indicate that nasal delivery of powder formulations with the addition of CMC-Na as an excipient is a promising approach for improving the nasal absorption of macromolecules.

  3. Development of a revised mathematical model of the gastrointestinal tract

    International Nuclear Information System (INIS)

    Barker, A.

    1991-01-01

    The objectives of this research are as follows. First, to incorporate new biological data into a revised mathematical adult gastrointestinal tract model that includes: ingestion in both liquid and solid forms; consideration of absorption in the stomach, small intestine, ascending colon, transverse colon or not at all; gender and age of the adult; and whether the adult is a smoker or not. Next, to create a computer program in basic language for calculating residence times in each anatomical section of the GI tract for commonly used radionuclides. Also, to compare and contrast the new model with the ICRP 30 GI tract model in terms of physiological concepts, mathematical concepts, and revised residence times for several commonly used radionuclides. Finally, to determine whether the new model is sufficiently better than the current model to warrant its use as a replacement for the Eve model

  4. Carbohydrate-Dependent, Exercise-Induced Gastrointestinal Distress

    Directory of Open Access Journals (Sweden)

    Erick Prado de Oliveira

    2014-10-01

    Full Text Available Gastrointestinal (GI problems are a common concern of athletes during intense exercise. Ultimately, these symptoms can impair performance and possibly prevent athletes from winning or even finishing a race. The main causes of GI problems during exercise are mechanical, ischemic and nutritional factors. Among the nutritional factors, a high intake of carbohydrate and hyperosmolar solutions increases GI problems. A number of nutritional manipulations have been proposed to minimize gastrointestinal symptoms, including the use of multiple transportable carbohydrates. This type of CHO intake increases the oxidation rates and can prevent the accumulation of carbohydrate in the intestine. Glucose (6% or glucose plus fructose (8%–10% beverages are recommended in order to increase CHO intake while avoiding the gastric emptying delay. Training the gut with high intake of CHO may increase absorption capacity and probably prevent GI distress. CHO mouth rinse may be a good strategy to enhance performance without using GI tract in exercises lasting less than an hour. Future strategies should be investigated comparing different CHO types, doses, and concentration in exercises with the same characteristics.

  5. Uranium absorption study pile

    International Nuclear Information System (INIS)

    Raievski, V.; Sautiez, B.

    1959-01-01

    The report describes a pile designed to measure the absorption of fuel slugs. The pile is of graphite and comprises a central section composed of uranium rods in a regular lattice. RaBe sources and BF 3 counters are situated on either side of the center. A given uranium charge is compared with a specimen charge of about 560 kg, and the difference in absorption between the two noted. The sensitivity of the equipment will detect absorption variations of about a few ppm boron (10 -6 boron per gr. of uranium) or better. (author) [fr

  6. Total photon absorption

    International Nuclear Information System (INIS)

    Carlos, P.

    1985-06-01

    The present discussion is limited to a presentation of the most recent total photonuclear absorption experiments performed with real photons at intermediate energy, and more precisely in the region of nucleon resonances. The main sources of real photons are briefly reviewed and the experimental procedures used for total photonuclear absorption cross section measurements. The main results obtained below 140 MeV photon energy as well as above 2 GeV are recalled. The experimental study of total photonuclear absorption in the nuclear resonance region (140 MeV< E<2 GeV) is still at its beginning and some results are presented

  7. Alimentary tract absorption (f1 values) for radionuclides in local and regional fallout from nuclear tests.

    Science.gov (United States)

    Ibrahim, Shawki A; Simon, Steven L; Bouville, André; Melo, Dunstana; Beck, Harold L

    2010-08-01

    This paper presents gastrointestinal absorption fractions (f1 values) for estimating internal doses from local and regional fallout radionuclides due to nuclear tests. The choice of f1 values are based on specific circumstances of weapons test conditions and a review of reported f1 values for elements in different physical and chemical states. Special attention is given to fallout from nuclear tests conducted at the Marshall Islands. We make a distinction between the f1 values for intakes of radioactive materials immediately after deposition (acute intakes) and intakes that occur in the course of months and years after deposition, following incorporation into terrestrial and aquatic foodstuffs (chronic intakes). Multiple f1 values for different circumstances where persons are exposed to radioactive fallout (e.g., local vs. regional fallout and coral vs. continental tests) are presented when supportive information is available. In some cases, our selected f1 values are similar to those adopted by the International Commission on Radiological Protection (ICRP) (e.g., iodine and most actinides). However, f1 values for cesium and strontium derived from urine bioassay data of the Marshallese population are notably lower than the generic f1 values recommended by ICRP, particularly for acute intakes from local fallout (0.4 and 0.05 for Cs and Sr, respectively). The f1 values presented here form the first complete set of values relevant to realistic dose assessments for exposure to local or regional radioactive fallout.

  8. Fractional smith chart theory

    KAUST Repository

    Shamim, Atif

    2011-03-01

    For the first time, a generalized Smith chart is introduced here to represent fractional order circuit elements. It is shown that the standard Smith chart is a special case of the generalized fractional order Smith chart. With illustrations drawn for both the conventional integer based lumped elements and the fractional elements, a graphical technique supported by the analytical method is presented to plot impedances on the fractional Smith chart. The concept is then applied towards impedance matching networks, where the fractional approach proves to be much more versatile and results in a single element matching network for a complex load as compared to the two elements in the conventional approach. © 2010 IEEE.

  9. Food and symptom generation in functional gastrointestinal disorders: physiological aspects.

    Science.gov (United States)

    Farré, Ricard; Tack, Jan

    2013-05-01

    The response of the gastrointestinal tract (GIT) to ingestion of food is a complex and closely controlled process, which allows optimization of propulsion, digestion, absorption of nutrients, and removal of indigestible remnants. This review summarizes current knowledge on the mechanisms that control the response of the GIT to food intake. During the cephalic phase, triggered by cortical food-related influences, the GIT prepares for receiving nutrients. The gastric phase is dominated by the mechanical effect of the meal volume. Accumulation of food in the stomach activates tension-sensitive mechanoreceptors, which in turn stimulate gastric accommodation and gastric acid secretion through the intrinsic and vago-vagal reflex pathways. After meal ingestion, the tightly controlled process of gastric emptying starts, with arrival of nutrients in the duodenum triggering negative feedback on emptying and stimulating secretion of digestive enzymes through the neural (mainly vago-vagal reflex, but also intrinsic) and endocrine (release of peptides from entero-endocrine cells) pathways. Several types of specialized receptors detect the presence of all main categories of nutrients. In addition, the gastrointestinal mucosa expresses receptors of the T1R and T2R families (taste receptors) and several members of the transient receptor potential channel family, all of which are putatively involved in the detection of specific tastants in the lumen. Activation of nutrient and taste sensors also activates the extrinsic and intrinsic neural, as well as entero-endocrine, pathways. During passage through the small bowel, nutrients are progressively extracted, and electrolyte-rich liquid intestinal content with non-digestible residue is delivered to the colon. The colon provides absorption of the water and electrolytes, storage of non-digestible remnants of food, aboral propulsion of contents, and finally evacuation through defecation.

  10. Fractional factorial plans

    CERN Document Server

    Dey, Aloke

    2009-01-01

    A one-stop reference to fractional factorials and related orthogonal arrays.Presenting one of the most dynamic areas of statistical research, this book offers a systematic, rigorous, and up-to-date treatment of fractional factorial designs and related combinatorial mathematics. Leading statisticians Aloke Dey and Rahul Mukerjee consolidate vast amounts of material from the professional literature--expertly weaving fractional replication, orthogonal arrays, and optimality aspects. They develop the basic theory of fractional factorials using the calculus of factorial arrangements, thereby providing a unified approach to the study of fractional factorial plans. An indispensable guide for statisticians in research and industry as well as for graduate students, Fractional Factorial Plans features: * Construction procedures of symmetric and asymmetric orthogonal arrays. * Many up-to-date research results on nonexistence. * A chapter on optimal fractional factorials not based on orthogonal arrays. * Trend-free plans...

  11. Fractional Dynamics and Control

    CERN Document Server

    Machado, José; Luo, Albert

    2012-01-01

    Fractional Dynamics and Control provides a comprehensive overview of recent advances in the areas of nonlinear dynamics, vibration and control with analytical, numerical, and experimental results. This book provides an overview of recent discoveries in fractional control, delves into fractional variational principles and differential equations, and applies advanced techniques in fractional calculus to solving complicated mathematical and physical problems.Finally, this book also discusses the role that fractional order modeling can play in complex systems for engineering and science. Discusses how fractional dynamics and control can be used to solve nonlinear science and complexity issues Shows how fractional differential equations and models can be used to solve turbulence and wave equations in mechanics and gravity theories and Schrodinger’s equation  Presents factional relaxation modeling of dielectric materials and wave equations for dielectrics  Develops new methods for control and synchronization of...

  12. Diagnostic evaluatuin of gastrointestinal tumors

    International Nuclear Information System (INIS)

    Linke, R.; Tatsch, K.

    1998-01-01

    Prior to surgery of gastrointestinal tumors exact information about tumor localization, extent and possible infiltration in adjacent structures are important. The task for radiological and scintigraphic methods is predominantly the preoperative tumor staging. The upper (esophagus, stomach, duodenum) and the lower (colon, rectum) gastrointestinal tract should be routinely investigated by endoscopy and endosonography. CT or MRI imaging may add information about tumor extent, infiltration in adjacent structures and pathologically enlarged lymph nodes. The latter may be detected with similar or higher sensitivity by PET as well. Furthermore, with PET it is possible to differentiate a tumor recurrence from postoperative scar tissue earlier than with conventional morphological imaging techniques, for example in colorectal cancer. Liver tumors should primarily be inspected sonographically followed by an MRI scan if dignity is uncertain. The receptor scintigraphy with radioactive ligands allows to further characterize a detected tumor. Benigne liver lesions can be distinguished from malignant tumors (metastasis, hepatocellular carcinoma [HCC]) by the neogalactoalbumin-(NGA-)scintigraphy, because NGA binds exclusively to the liver galactose receptors of normally functioning hepatocytes. For the differentiation between liver metastasis and HCC insulin scintigraphy can be used, since insulin binds significantly in HCC due to an overexpression of insulin receptors in these tumors. If a malignant process is suspected, additionally CT-arterioportography may be recommended, because this newer radiological technique is capable to visualize lesions smaller than 1 cm. In such cases PET is sensitive as well and due to increased glucose metabolism even small foci can be detected with comparably high sepcificity. The method of choice for the detection of a pancreatic tumor is endoscopic sonography. In most cases the dignity of the tumor can be verified by ERCP, but sometimes it is very

  13. Absorption heat pump system

    Science.gov (United States)

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  14. Zeeman atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Hadeishi, T.; McLaughlin, R.

    1978-08-01

    The design and development of a Zeeman atomic absorption spectrometer for trace element analysis are described. An instruction manual is included which details the operation, adjustment, and maintenance. Specifications and circuit diagrams are given

  15. Revisiting Absorptive Capacity

    DEFF Research Database (Denmark)

    de Araújo, Ana Luiza Lara; Ulhøi, John Parm; Lettl, Christopher

    Absorptive capacity has mostly been perceived as a 'passive' outcome of R&D investments. Recently, however, a growing interest into its 'proactive' potentials has emerged. This paper taps into this development and proposes a dynamic model for conceptualizing the determinants of the complementary...... learning processes of absorptive capacity, which comprise combinative and adaptive capabilities. Drawing on survey data (n=169), the study concludes that combinative capabilities primarily enhance transformative and exploratory learning processes, while adaptive capabilities strengthen all three learning...

  16. Comment on resonant absorption

    International Nuclear Information System (INIS)

    Hammerling, P.

    1977-01-01

    An average over angles of incidence of the usual resonant absorption function is presented. This form is appropriate under experimental conditions where the angles of incidence vary greatly and in an unknown manner. For comparison a lens-ellipsoidal mirror illumination system with a known longitudinal aberration is considered. In the latter example the angles of incidence are readily obtained and the resulting resonance absorption function evaluated. The associated fields are calculated in a similar fashion. (author)

  17. Optical absorption measurement system

    International Nuclear Information System (INIS)

    Draggoo, V.G.; Morton, R.G.; Sawicki, R.H.; Bissinger, H.D.

    1989-01-01

    This patent describes a non-intrusive method for measuring the temperature rise of optical elements under high laser power optical loading to determine the absorption coefficient. The method comprises irradiating the optical element with a high average power laser beam, viewing the optical element with an infrared camera to determine the temperature across the optical element and calculating the absorption of the optical element from the temperature

  18. Thermal properties of carbon black aqueous nanofluids for solar absorption

    Directory of Open Access Journals (Sweden)

    Han Dongxiao

    2011-01-01

    Full Text Available Abstract In this article, carbon black nanofluids were prepared by dispersing the pretreated carbon black powder into distilled water. The size and morphology of the nanoparticles were explored. The photothermal properties, optical properties, rheological behaviors, and thermal conductivities of the nanofluids were also investigated. The results showed that the nanofluids of high-volume fraction had better photothermal properties. Both carbon black powder and nanofluids had good absorption in the whole wavelength ranging from 200 to 2,500 nm. The nanofluids exhibited a shear thinning behavior. The shear viscosity increased with the increasing volume fraction and decreased with the increasing temperature at the same shear rate. The thermal conductivity of carbon black nanofluids increased with the increase of volume fraction and temperature. Carbon black nanofluids had good absorption ability of solar energy and can effectively enhance the solar absorption efficiency.

  19. Biotin absorption by distal rat intestine

    International Nuclear Information System (INIS)

    Bowman, B.B.; Rosenberg, I.H.

    1987-01-01

    We used the in vivo intestinal loop approach, with short (10-min) and long (3-h) incubations, to examine biotin absorption in proximal jejunum, distal ileum, cecum and proximal colon. In short-term studies, luminal biotin disappearance from rat ileum was about half that observed in the jejunum, whereas absorption by proximal colon was about 12% of that in the jejunum. In 3-h closed-loop studies, the absorption of 1.0 microM biotin varied regionally. Biotin absorption was nearly complete in the small intestine after 3 h; however, only about 15% of the dose had been absorbed in the cecum and 27% in the proximal colon after 3 h. Independent of site of administration, the major fraction of absorbed biotin was recovered in the liver; measurable amounts of radioactive biotin were also present in kidney and plasma. The results support the potential nutritional significance for the rat of biotin synthesized by bacteria in the distal intestine, by demonstrating directly an absorptive capability of mammalian large bowel for this vitamin

  20. Effects of boiling and in vitro gastrointestinal digestion on the antioxidant activity of Sonchus oleraceus leaves.

    Science.gov (United States)

    Mawalagedera, S M M R; Ou, Zong-Quan; McDowell, Arlene; Gould, Kevin S

    2016-03-01

    Leaves of Sonchus oleraceus L. are especially rich in phenolic compounds and have potent extractable antioxidants. However, it is not known how their antioxidant activity changes after cooking and gastrointestinal digestion. We recorded the profile of phenolics and their associated antioxidant activity in both raw and boiled S. oleraceus leaf extracts after in vitro gastric and intestinal digestion, and quantified their antioxidant potentials using Caco-2 and HepG2 cells. Boiling significantly diminished the oxygen radical absorbance capacity (ORAC) and concentrations of ascorbate and chicoric acid in the soluble fractions. In contrast, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and concentrations of caftaric and chlorogenic acids were unaffected. Phenolics in the soluble fraction were absorbed into cultured human cells and exerted antioxidant activity. Only chlorogenic acid content remained stable during gastrointestinal digestion. S. oleraceus appears to be an excellent dietary source of phenolic antioxidants.

  1. Phytotherapy in Functional Gastrointestinal Disorders.

    Science.gov (United States)

    Kelber, Olaf; Bauer, Rudolf; Kubelka, Wolfgang

    2017-01-01

    Phytotherapy is an important therapeutic option in functional gastrointestinal diseases (FGID). It has a large tradition, with different approaches in different regions of the world, some of which have made their way into modern evidence-based medicine (EBM). Taking into account the number of herbs in use, and also the cumulated scientific evidence on them, FGID are possibly the most important indication in phytotherapy. This does not only apply for European phytotherapy, but also for other regions, such as Asia. Within European phytotherapy, herbs active in FGID are usually classified according to their main active constituents and their activities. Typically, the herbs used in FGID are grouped into amara, aromatica, amara aromatica combining both properties, herbs stimulating gastric secretion, herbs containing spasmolytic and carminative essential oils or spasmolytic alkaloids, mucilaginosa soothing the mucosa, and flavonoid containing drugs with anti-inflammatory properties. In phytotherapy, different plants are frequently combined to maximize effectiveness and specificity of action. Very potent combination products can be developed when the mechanisms of action of the combination partners are complementary. This approach can be demonstrated by the example of STW 5. For this herbal combination product, therapeutic efficacy in FGID has been clinically proven according to the highest standards of EBM. This example also underlines that modern rational phytotherapy is definitely part of modern EBM. Key Messages: FGID is one of the most important indications in phytotherapy and rationally combined herbal preparations are established evidence-based therapeutic options. © 2018 The Author(s) Published by S. Karger AG, Basel.

  2. Microrobotics for future gastrointestinal endoscopy.

    Science.gov (United States)

    Menciassi, Arianna; Quirini, Marco; Dario, Paolo

    2007-01-01

    The impulse given by robotic technologies and imaging techniques to the development of a new way to conceive and perform surgery is clearly visible. Nowadays, minimally invasive surgical (MIS) procedures are often performed with the assistance of robots, such as the Da Vinci master-slave system, the AESOP robot with voice control, etc. In addition, mechatronic technologies are becoming the elective technologies for designing advanced hand-held surgical tools. The introduction of robotic technologies in endoscopy has been slower than in MIS, since the development of miniaturized robotic components for entering the small orifices of the human body is difficult. On the other hand, the large contribution that robotic technologies could bring to endoluminal techniques has been evident since the first development of instrumented catheters. In the 1990s, there was an increasing activity in the application of robotic technologies to improve endoscopic procedures in the gastrointestinal tract. The objective of robotic colonoscopy and gastroscopy was to obtain more effective diagnoses in terms of reduced pain for the patients, and to make uniform the diagnostic procedures, which too often depended on the manual abilities of the endoscopist. Currently, the availability of more reliable robotic technologies for miniaturization of size and integration of functions has allowed to conceive and develop robotic pills for the early screening of the digestive tract, with dramatic potential advantages for patients, endoscopists, and healthcare system.

  3. Multicentric malignant gastrointestinal stromal tumor

    International Nuclear Information System (INIS)

    Shukla, Shailaja; Singh, Sanjeet K; Pujani, Mukta

    2009-01-01

    Malignant gastrointestinal stromal tumor (GIST) is a rare type of sarcoma that is found in the digestive system, most often in the wall of the stomach. Multiple GISTs are extremely rare and usually associated with type 1 neurofibromatosis and familial GIST. We report here a case of a 70-year-old woman who reported pain in the abdomen, loss of appetite, and weight loss for six months. Ultrasound examination showed a small bowel mass along with multiple peritoneal deposits and a mass within the liver. Barium studies were suggestive of a neoplastic pathology of the distal ileum. A differential diagnosis of adenocarcinoma/lymphoma with metastases was entertained. Perioperative findings showed two large growths arising from the jejunum and the distal ileum, along with multiple smaller nodules on the serosal surface and adjoining mesentery of the involved bowel segments. Segmental resection of the involved portions of the intestine was performed. Histopathological features were consistent with those of multicentric malignant GIST-not otherwise specified (GIST-NOS). Follow-up examination three months after surgery showed no evidence of recurrence. (author)

  4. Immunoscintigraphy of gastrointestinal tract carcinomas

    International Nuclear Information System (INIS)

    Mladenov, B.; Peshev, N.

    1995-01-01

    The results of labelled monoclonal antibodies (MoA) immunoscintigraphy in malignant tumors involving the gastrointestinal tract are presented. The obtained data have an essential practical bearing on the early diagnosis and radical treatment undertaken. Immunoscintigraphy is performed with Imacis-I ( 131 I, monoclonal antibody, 19-9 F(ab') 2 anti-CEA F(ab') 2 ) obtained from the CIS company, and Jodomab-R-2( 131 I, anti-CEA monoclonal antibody F(ab') 2 ) of the Sorin Biomedica Company, inserted at activity ranging from 11 to 185 MBq. Scanning by a planar gamma-camera is performed at 72 hours. A total of twenty-four patients are examined: 14 preoperatively (with gastric cancer - 2, pancreatic cancer - 1 and location of the neoplasm in different segments of the colon - 11), and ten postoperatively. Positive results are obtained in twenty-two (92 per cent) of the total number of patients under study. In twelve (86 per cent) of those examined preoperatively intensive accumulation of labelled autoantibodies in the cancer area is documented with a negative result recorded in two cases only. Metastases are found in two patients operated on, while in the remainder the results are negative and consistent with those of the other methods of examination. 13 refs., 4 figs. (author)

  5. [Functional and motor gastrointestinal disorders].

    Science.gov (United States)

    Mearin, Fermín; Rey, Enrique; Balboa, Agustín

    2015-09-01

    This article discusses the most interesting studies on functional and motor gastrointestinal disorders presented at Digestive Diseases Week (DDW), 2015. Researchers are still seeking biomarkers for irritable bowel syndrome and have presented new data. One study confirmed that the use of low-dose antidepressants has an antinociceptive effect without altering the psychological features of patients with functional dyspepsia. A contribution that could have immediate application is the use of transcutaneous electroacupuncture, which has demonstrated effectiveness in controlling nausea in patients with gastroparesis. New data have come to light on the importance of diet in irritable bowel syndrome, although the effectiveness of a low-FODMAP diet seems to be losing momentum with time. Multiple data were presented on the long-term efficacy of rifaximin therapy in patients with irritable bowel syndrome and diarrhoea. In addition, among other contributions, and more as a curiosity, a study evaluated the effect of histamine in the diet of patients with irritable bowel syndrome. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  6. Gastrointestinal disturbances in marathon runners.

    Science.gov (United States)

    Riddoch, C; Trinick, T

    1988-06-01

    The purpose of this survey was to investigate the prevalence of running-induced gastrointestinal (GI) disturbances in marathon runners. A questionnaire was completed by 471 of the estimated 1,750 competitors in the 1986 Belfast City Marathon. Eighty-three per cent of respondents indicated that they occasionally or frequently suffered one or more GI disturbances during or immediately after running. The urge to have a bowel movement (53%) and diarrhoea (38%) were the most common symptoms, especially among female runners (74% and 68% respectively). Upper GI tract symptoms were experienced more by women than men (p less than 0.05) and more by younger runners than older runners (p less than 0.01). Women also suffered more lower GI tract symptoms than men (p less than 0.05) with younger runners showing a similar trend. Both upper and lower tract symptoms were more common during a "hard" run than an "easy" run (p less than 0.01) and were equally as common both during and after running. Of those runners who suffered GI disturbances, 72% thought that running was the cause and 29% believed their performance to be adversely affected. There was no consensus among sufferers as to the causes of symptoms and a wide variety of "remedies" were suggested. GI disturbances are common amongst long-distance runners and their aetiology is unknown. Medical practitioners should be aware of this when dealing with patients who run.

  7. Dividing Fractions: A Pedagogical Technique

    Science.gov (United States)

    Lewis, Robert

    2016-01-01

    When dividing one fraction by a second fraction, invert, that is, flip the second fraction, then multiply it by the first fraction. To multiply fractions, simply multiply across the denominators, and multiply across the numerators to get the resultant fraction. So by inverting the division of fractions it is turned into an easy multiplication of…

  8. Transcatheter Arterial Embolization for Gastrointestinal Bleeding Secondary to Gastrointestinal Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Lin [Henan Cancer Hospital, The Affiliated Cancer Hospital of Zhengzhou University, Department of Radiology (China); Shin, Ji Hoon, E-mail: jhshin@amc.seoul.kr; Han, Kichang; Tsauo, Jiaywei; Yoon, Hyun-Ki; Ko, Gi-Young [University of Ulsan, College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology (Korea, Republic of); Shin, Jong-Soo [Kyunghee University, College of Medicine, Kangdong Kyunghee University Hospital, Department of Radiology (Korea, Republic of); Sung, Kyu-Bo [University of Ulsan, College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology (Korea, Republic of)

    2016-11-15

    PurposeTo evaluate the effectiveness of transcatheter arterial embolization (TAE) for gastrointestinal (GI) bleeding caused by GI lymphoma.Materials and MethodsThe medical records of 11 patients who underwent TAE for GI bleeding caused by GI lymphoma between 2001 and 2015 were reviewed retrospectively.ResultsA total of 20 TAE procedures were performed. On angiography, contrast extravasation, and both contrast extravasation and tumor staining were seen in 95 % (19/20) and 5 % (1/20) of the procedures, respectively. The most frequently embolized arteries were jejunal (n = 13) and ileal (n = 5) branches. Technical and clinical success rates were 100 % (20/20) and 27 % (3/11), respectively. The causes of clinical failure in eight patients were rebleeding at new sites. In four patients who underwent repeat angiography, the bleeding focus was new each time. Three patients underwent small bowel resection due to rebleeding after one (n = 2) or four (n = 1) times of TAEs. Another two patients underwent small bowel resection due to small bowel ischemia/perforation after three or four times of TAEs. The 30-day mortality rate was 18 % due to hypovolemic shock (n = 1) and multiorgan failure (n = 1).ConclusionAngiogram with TAE shows limited therapeutic efficacy to manage GI lymphoma-related bleeding due to high rebleeding at new sites. Although TAE can be an initial hemostatic measure, surgery should be considered for rebleeding due to possible bowel ischemic complication after repeated TAE procedures.

  9. Fraction of a dose absorbed estimation for structurally diverse low solubility compounds.

    Science.gov (United States)

    Sugano, Kiyohiko

    2011-02-28

    The purpose of the present study was to investigate the prediction accuracy of the fully mechanistic gastrointestinal unified theoretical (GUT) framework for in vivo oral absorption of low solubility drugs. Solubility in biorelevant media, molecular weight, logP(oct), pK(a), Caco-2 permeability, dose and particle size were used as the input parameters. To neglect the effect of the low stomach pH on dissolution of a drug, the fraction of a dose absorbed (Fa%) of undissociable and free acids were used. In addition, Fa% of free base drugs with the high pH stomach was also included to increase the number of model drugs. In total twenty nine structurally diverse compounds were used as the model drugs. Fa% data at several doses and particle sizes in humans and dogs were collated from the literature (total 110 Fa% data). In approximately 80% cases, the prediction error was within 2 fold, suggesting that the GUT framework has practical predictability for drug discovery, but not for drug development. The GUT framework appropriately captured the dose and particle size dependency of Fa% as the particle drifting effect was taken into account. It should be noted that the present validation results cannot be applied for salt form cases and other special formulations such as solid dispersions and emulsion formulations. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. Absorption of cadmium in the newborn and juvenile guinea pig

    International Nuclear Information System (INIS)

    Sasser, L.B.; Jarboe, G.E.

    1978-01-01

    The accepted premise that absorption is enhanced in the newborn animal is based primarily on studies using the rat, which has a relatively immature gastrointestinal system at birth. This study was conducted to determine if enhanced absorption of cadmium also occurs in the guinea pig, a species that is more precocious at birth than the rat. Newborn guinea pigs were administered a single oral dose of 5 μCi of /sup 115m/Cd (0.25 mCi of /sup 115m/Cd per milligram of cadmium) between 8 and 24 hr of age and killed at intervals between 1 and 14 days after the dosing. Juvenile guinea pigs were similarly dosed with 20 μCi of /sup 115m/Cd and killed 1 to 5 days later. Guinea pigs dosed on the day of birth absorbed approximately 6% of the dose by 1 day after the dosing and nearly 25% of the dose by 11 days. This is a cumulative absorption five times that found in rats dosed at 24 hr and two times that of rats dosed at 2 hr. The residence time of cadmium in the gastrointestinal tract was longer in newborn guinea pigs than in juvenile guinea pigs but was still significantly less than that in the newborn rat. We concluded that the absorption of cadmium from the gastrointestinal tract was greater in newborn guinea pigs than in rats, even though the residence time of cadmium in the intestinal tract was less in guinea pigs than in rats and the maturity at birth of the guinea pig is greater than that of the rat. The bases of these differences were not readily apparent

  11. Drugs Approved for Gastrointestinal Stromal Tumors

    Science.gov (United States)

    This page lists cancer drugs approved by the Food and Drug Administration (FDA) for gastrointestinal stromal tumors (GIST). The list includes generic names and brand names. The drug names link to NCI's Cancer Drug Information summaries.

  12. Spontaneous neonatal gastrointestinal perforation: surgical or ...

    African Journals Online (AJOL)

    ... cases of spontaneous gastrointestinal perforation in neonates at the University of Benin Teaching Hospital, Benin City. The perinatal stress factors were caesarian delivery, prematurity and fetal distress due to prolonged obstructed labour.

  13. METHOD OF SUPPRESSING GASTROINTESTINAL UREASE ACTIVITY

    Science.gov (United States)

    Visek, W.J.

    1963-04-23

    This patent shows a method of increasing the growth rate of chicks. Certain diacyl substituted ureas such as alloxan, murexide, and barbituric acid are added to their feed, thereby suppressing gastrointestinal urease activity and thus promoting growth. (AEC)

  14. Gastro-intestinal phytobezoars in Zimbabwean Africans.

    Science.gov (United States)

    Stein, C M; Gelfand, M

    1985-01-01

    The clinical features of 10 African patients with gastro-intestinal phytobezoars are described. These were similar to those described with persimmon bezoars and we postulate that the fruit of locally found trees, also of the genus Diospyros, are responsible.

  15. International Foundation for Functional Gastrointestinal Disorders

    Science.gov (United States)

    ... Survey Corner News Medical and Treatment News Events Press Releases Commentary For Media ... IFFGD is your resource for reliable digestive health knowledge, support, and assistance about functional gastrointestinal (GI) and ...

  16. Gastrointestinal Epithelial Organoid Cultures from Postsurgical Tissues.

    Science.gov (United States)

    Hahn, Soojung; Yoo, Jongman

    2017-08-17

    An organoid is a cellular structure three-dimensionally (3D) cultured from self-organizing stem cells in vitro, which has a cell population, architectures, and organ specific functions like the originating organs. Recent advances in the 3D culture of isolated intestinal crypts or gastric glands have enabled the generation of human gastrointestinal epithelial organoids. Gastrointestinal organoids recapitulate the human in vivo physiology because of all the intestinal epithelial cell types that differentiated and proliferated from tissue resident stem cells. Thus far, gastrointestinal organoids have been extensively used for generating gastrointestinal disease models. This protocol describes the method of isolating a gland or crypt using stomach or colon tissue after surgery and establishing them into gastroids or colonoids.

  17. Prolonged parenteral nutrition after neonatal gastrointestinal surgery

    DEFF Research Database (Denmark)

    Estmann, Anne; Qvist, Niels; Husby, Steffen

    2002-01-01

    to diagnosis and clinical course. METHODOLOGY: This study reviews the clinical course of infants with gastrointestinal disease (gastroschisis, intestinal atresia, omphalocele, volvulus, Hirschsprung's disease and necrotizing enterocolitis) with a prolonged need for parenteral nutrition in the Western part...

  18. Comparative Molecular Analysis of Gastrointestinal Adenocarcinomas

    NARCIS (Netherlands)

    Liu, Yang; Sethi, Nilay S; Hinoue, Toshinori; Schneider, Barbara G; Cherniack, Andrew D; Sanchez-Vega, Francisco; Seoane, Jose A; Farshidfar, Farshad; Bowlby, Reanne; Islam, Mirazul; Kim, Jaegil; Chatila, Walid; Akbani, Rehan; Kanchi, Rupa S; Rabkin, Charles S; Willis, Joseph E; Wang, Kenneth K; McCall, Shannon J; Mishra, Lopa; Ojesina, Akinyemi I; Bullman, Susan; Pedamallu, Chandra Sekhar; Lazar, Alexander J; Sakai, Ryo; Thorsson, Vésteinn; Bass, Adam J; Laird, Peter W; de Krijger, RR

    2018-01-01

    We analyzed 921 adenocarcinomas of the esophagus, stomach, colon, and rectum to examine shared and distinguishing molecular characteristics of gastrointestinal tract adenocarcinomas (GIACs). Hypermutated tumors were distinct regardless of cancer type and comprised those enriched for

  19. Appropriateness of Referrals for Upper Gastrointestinal Endoscopy ...

    African Journals Online (AJOL)

    Appropriateness of Referrals for Upper Gastrointestinal Endoscopy. ... Accra between January and December, 2008 were interviewed and evaluated for this study. ... Presentations with bleeding and suspicion of malignancy showed statistical ...

  20. New techniques in gastrointestinal endoscopic surgery

    Directory of Open Access Journals (Sweden)

    Rafael Antonio Luengas Tello

    2012-09-01

    Full Text Available Gastrointestinal endoscopic surgery has been making great progress since the seventies in the management paradigms of conditions such as gastrointestinal bleeding, polyp resection and diagnostic and therapeutic management of the biliary tract. The current challenge is the development of techniques that allow endoscopic treatment of emerging diseases such as cancer, morbid obesity, gastro-esophageal reflux and achalasia. This article reports on new techniques and expectations for the future in the endoscopic management of these diseases.

  1. Rare upper gastrointestinal hemorrhage of cetuximab

    OpenAIRE

    Duan, Shi-Jie; Gao, Zi-Ming; Wang, Peng-Liang; Gong, Bao-Cheng; Huang, Han-Wei; Luo, Lei; Wang, Xin; Xing, Ya-Nan; Xu, Hui-Mian; Liu, Fu-Nan

    2017-01-01

    Abstract Rationale: cetuximab, an epidermal growth factor receptor inhibitor, is a targeted therapeutic regimen of colorectal cancers. Several common adverse effects have been found, such as cutaneous or gastrointestinal toxicity. However, according to the articles had been published, upper gastrointestinal bleeding (UGIB) is considered to be rare and its mechanism remains unclear. Patient concerns: In this report, we presented a 42-year-old male patient with advanced recto-sigmoid cancer. Af...

  2. Sedation-related complications in gastrointestinal endoscopy

    OpenAIRE

    Amornyotin, Somchai

    2013-01-01

    Sedation practices for gastrointestinal endoscopic (GIE) procedures vary widely in different countries depending on health system regulations and local circumstances. The goal of procedural sedation is the safe and effective control of pain and anxiety, as well as to provide an appropriate degree of memory loss or decreased awareness. Sedation-related complications in gastrointestinal endoscopy, once occurred, can lead to significant morbidity and occasional mortality in patients. The risk fa...

  3. Gastrointestinal Stromal Tumor of the Esophagus: Report of a Case

    OpenAIRE

    Mehmet Erol

    2014-01-01

    Gastrointestinal stromal tumors are rare neoplasms to be thought to arise from mesenchymal cells of the gastrointestinal tract. Gastrointestinal stromal tumors (GIST) of the esophagus are well documented but are very much rarer than gastrointestinal stromal tumors of the stomach and small bowel. We describe a case of GIST of the esophagus that was resected with wide surgical resection.

  4. Gastrointestinal function in chronic radiation enteritis -effects of loperamide-N-oxide

    International Nuclear Information System (INIS)

    Yeoh, E.K.; Horowitz, M.; Russo, A.; Muecke, T.; Chatterton, B.E.; Robb, T.

    1993-01-01

    The effects of loperamide-N-oxide, a new peripheral opiate agonist precursor, on gastrointestinal function were evaluated in 18 patients with diarrhoea caused by radiation enteritis. Each patient was given loperamide-N-oxide and placebo for 14 days, separated by a washout period of 14 days. Gastrointestinal symptoms; absorption of bile acid, vitamin B12, lactose, and fat; gastric emptying; small intestinal and whole gut transit; and intestinal permeability were measured during placebo and loperamide-N-oxide phases. Data were compared with those obtained in 18 normal subjects. In the patient, in addition to an increased frequency of bowel actions there was reduced bile acid absorption, higher prevalence of lactose malabsorption associated with a reduced dietary intake of dairy products and faster small intestinal and whole gut transit when compared with the normal subjects. There was no significant difference in gastric emptying between the two groups. Treatment with loperamide-N-oxide was associated with a reduced frequency of bowel actions, slower small intestinal and total gut transit, more rapid gastric emptying improved absorption of bile acid and increased permeability to 51 Cr EDTA. These observations indicate that: (1) diarrhoea caused by chronic radiation enteritis is associated with more rapid intestinal transit and a high prevalence of bile acid and lactose malabsorption, and (2) loperamide-N-oxide slows small intestinal transit, increases bile acid absorption, and is effective in the treatment of diarrhoea associated with chronic radiation enteritis. (Author)

  5. Radiation injury of the gastrointestinal tract. Pathogenesis, protection and treatment

    International Nuclear Information System (INIS)

    Svoboda, V.; Mandel, L.

    1990-01-01

    The review deals in detail with all aspects of the gastrointestinal syndrome following irradiation with various doses. After the action of low doses, 10 to 15 Gy, a fraction of unaffected hemopoietic tissues remains preserved, and spontaneous repair of the intestinal mucosa and survival take place. In the first 24 hours after irradiation, the following symptoms appear: vomiting, anorexia, arterial pressure drop, tachycardia, blockage of gastric secretion, hyperglycemia, blockage of mitoses in the active tissues, increased secretion of urea, etc. In 24 to 72 hours after irradiation, seeming adjustment takes place and depletion of the intestinal mucosa sets in. In 72 hours, edema of the submucosa, hemorrhage and diarrhea appear and depletion of lymphatic tissues commences. The last stage is agony and death. A detailed description is given of the kinetics of the intestinal epithelium and of its changes following irradiation, changes in the resorption and in the enzymatic activity of the intestine and of infections. Changes in the bile are also described. The various methods of treating the gastrointestinal syndrome are discussed; these include a dietary regimen, hypoxia, acholia, temporary ligation of the pancreatic duct, and chemoprotection. (M.D.). 195 refs

  6. Changes in mouse gastrointestinal microbial ecology with ingestion of kale.

    Science.gov (United States)

    Uyeno, Y; Katayama, S; Nakamura, S

    2014-09-01

    Kale, a cultivar of Brassica oleracea, has attracted a great deal of attention because of its health-promoting effects, which are thought to be exerted through modulation of the intestinal microbiota. The present study was performed to investigate the effects of kale ingestion on the gastrointestinal microbial ecology of mice. 21 male C57BL/6J mice were divided into three groups and housed in a specific pathogen-free facility. The animals were fed either a control diet or experimental diets supplemented with different commercial kale products for 12 weeks. Contents of the caecum and colon of the mice were processed for the determination of active bacterial populations by a bacterial rRNA-based quantification method and short-chain fatty acids by HPLC. rRNAs of Bacteroides-Prevotella, the Clostridium coccoides-Eubacterium rectale group, and Clostridium leptum subgroup constituted the major fraction of microbiota regardless of the composition of the diet. The ratio of Firmicutes to Bacteroidetes was higher in the colon samples of one of the kale diet groups than in the control. The colonic butyrate level was also higher with the kale-supplemented diet. Overall, the ingestion of kale tended to either increase or decrease the activity of specific bacterial groups in the mouse gastrointestinal tract, however, the effect might vary depending on the nutritional composition.

  7. In vitro anthelmintic effects of Spigelia anthelmia protein fractions against Haemonchus contortus.

    Directory of Open Access Journals (Sweden)

    Sandra Alves Araújo

    Full Text Available Gastrointestinal nematodes are a significant concern for animal health and well-being, and anthelmintic treatment is mainly performed through the use of chemical products. However, bioactive compounds produced by plants have shown promise for development as novel anthelmintics. The aim of this study is to assess the anthelmintic activity of protein fractions from Spigelia anthelmia on the gastrointestinal nematode Haemonchus contortus. Plant parts were separated into leaves, stems and roots, washed with distilled water, freeze-dried and ground into a fine powder. Protein extraction was performed with sodium phosphate buffer (75 mM, pH 7.0. The extract was fractionated using ammonium sulfate (0-90% and extensively dialyzed. The resulting fractions were named LPF (leaf protein fraction, SPF (stem protein fraction and RPF (root protein fraction, and the protein contents and activities of the fractions were analyzed. H. contortus egg hatching (EHA, larval exsheathment inhibition (LEIA and larval migration inhibition (LMIA assays were performed. Proteomic analysis was conducted, and high-performance liquid chromatography (HPLC chromatographic profiles of the fractions were established to identify proteins and possible secondary metabolites. S. anthelmia fractions inhibited H. contortus egg hatching, with LPF having the most potent effects (EC50 0.17 mg mL-1. During LEIA, SPF presented greater efficiency than the other fractions (EC50 0.25 mg mL-1. According to LMIA, the fractions from roots, stems and leaves also reduced the number of larvae, with EC50 values of 0.11, 0.14 and 0.21 mg mL-1, respectively. Protein analysis indicated the presence of plant defense proteins in the S. anthelmia fractions, including protease, protease inhibitor, chitinase and others. Conversely, secondary metabolites were absent in the S. anthemia fractions. These results suggest that S. anthelmia proteins are promising for the control of the gastrointestinal nematode H

  8. Comparative study about doses and radiological protection in gastrointestinal fluoroscopy

    International Nuclear Information System (INIS)

    Caneravo, L.V.; Borges, J.C.; Carlos, M.T.; Koch, H.A.

    1996-01-01

    The Radiation Protection and Dosimetry Institute of the National Nuclear Energy Commission (IRD/CNEN) and the Radiodiagnostic Service of the Rio de Janeiro Federal University Hospital, have been engaged in the development of quality control programs applied to radiodiagnostics, one of them concerning gastrointestinal fluoroscopy. Since fluoroscopy examinations normally deal with high doses, they represent an important fraction of public exposure. They deserve special attention and the risks to patients should be considered individually, not only as a population statistics. Another target should be the search for procedures that reduce doses to patients and, therefore, reduce dose to medical staff involved. This work describes steps followed and results obtained in the estimation of doses for patients and physicians. Investigated examinations were esophagography, gastroduodenal seriographic and colon with double contrast media, using conventional equipment with fluorescent screens, carried on by physicians engaged in the first year of medical residence. (authors). 9 refs., 1 fig., 2 tabs

  9. The particulate passage rate, nutrient composition and fermentation characteristics across gastrointestinal tracts in lactating dairy cows fed three different forage source diets.

    Science.gov (United States)

    Wang, B; Gu, F F; Huang, X B; Liu, J X

    2018-04-19

    This study was conducted to investigate the particulate passage rate, nutrient characteristics and fermentation parameters across the gastrointestinal tract (GIT) in lactating dairy cows fed cereal straws in comparison with alfalfa hay. Eighteen multiparous Holstein cows were randomly assigned to one of three experimental diets consisting of 55% concentrate, 15% corn silage and 30% different forage sources as follows (% of dry matter [DM]): (i) 23% alfalfa hay and 7% Chinese wild rye hay (AH); (ii) 30% corn stover (CS); and (iii) 30% rice straw (RS). The Cr-mordanted corn silage-neutral detergent fibre was used to estimate the passage flow at week 14. After 14-week feeding, the animals were slaughtered to collect the gastrointestinal digesta. Dietary forage sources had little effect on the fractional passage rates in the rumen (range from 5.05 to 6.25%/hr) or hindgut (range from 4.49 to 5.24%/hr). Total volatile fatty acid (VFA) concentration in the caecum was highest, followed by the rumen, colon and rectum, and the lowest in the abomasum and duodenum, indicating that the large intestines, especially caecum, are the important positions for carbohydrate degradation. Greater proportion of propionate and butyrate and lower acetate were found in the AH compared to CS or RS in colon, but higher acetate in abomasum was found in the cows fed CS or RS compared to AH. In conclusion, cereal straw diets did not change the particulate passage rate in the rumen and hindgut which might be mainly due to the similar DM intake among these three diets. Different forage source diets significantly changed VFA proportion in the abomasum and colon, indicating the existence of different digestion or absorption rates in these tracts among the experimental diets. © 2018 Blackwell Verlag GmbH.

  10. Fractional distillation of oil

    Energy Technology Data Exchange (ETDEWEB)

    Jones, L D

    1931-10-31

    A method of dividing oil into lubricating oil fractions without substantial cracking by introducing the oil in a heated state into a fractionating column from which oil fractions having different boiling points are withdrawn at different levels, while reflux liquid is supplied to the top of the column, and additional heat is introduced into the column by contacting with the oil therein a heated fluid of higher monlecular weight than water and less susceptible to thermal decomposition than is the highest boiling oil fraction resulting from the distillation, or of which any products produced by thermal decomposition will not occur in the highest boiling distillate withdrawn from the column.

  11. Deep Learning in Gastrointestinal Endoscopy.

    Science.gov (United States)

    Patel, Vivek; Armstrong, David; Ganguli, Malika; Roopra, Sandeep; Kantipudi, Neha; Albashir, Siwar; Kamath, Markad V

    2016-01-01

    Gastrointestinal (GI) endoscopy is used to inspect the lumen or interior of the GI tract for several purposes, including, (1) making a clinical diagnosis, in real time, based on the visual appearances; (2) taking targeted tissue samples for subsequent histopathological examination; and (3) in some cases, performing therapeutic interventions targeted at specific lesions. GI endoscopy is therefore predicated on the assumption that the operator-the endoscopist-is able to identify and characterize abnormalities or lesions accurately and reproducibly. However, as in other areas of clinical medicine, such as histopathology and radiology, many studies have documented marked interobserver and intraobserver variability in lesion recognition. Thus, there is a clear need and opportunity for techniques or methodologies that will enhance the quality of lesion recognition and diagnosis and improve the outcomes of GI endoscopy. Deep learning models provide a basis to make better clinical decisions in medical image analysis. Biomedical image segmentation, classification, and registration can be improved with deep learning. Recent evidence suggests that the application of deep learning methods to medical image analysis can contribute significantly to computer-aided diagnosis. Deep learning models are usually considered to be more flexible and provide reliable solutions for image analysis problems compared to conventional computer vision models. The use of fast computers offers the possibility of real-time support that is important for endoscopic diagnosis, which has to be made in real time. Advanced graphics processing units and cloud computing have also favored the use of machine learning, and more particularly, deep learning for patient care. This paper reviews the rapidly evolving literature on the feasibility of applying deep learning algorithms to endoscopic imaging.

  12. Molecular Testing for Gastrointestinal Cancer

    Directory of Open Access Journals (Sweden)

    Hye Seung Lee

    2017-03-01

    Full Text Available With recent advances in molecular diagnostic methods and targeted cancer therapies, several molecular tests have been recommended for gastric cancer (GC and colorectal cancer (CRC. Microsatellite instability analysis of gastrointestinal cancers is performed to screen for Lynch syndrome, predict favorable prognosis, and screen patients for immunotherapy. The epidermal growth factor receptor (EGFR tyrosine kinase inhibitor has been approved in metastatic CRCs with wildtype RAS (KRAS and NRAS exon 2–4. A BRAF mutation is required for predicting poor prognosis. Additionally, amplification of human epidermal growth factor receptor 2 (HER2 and MET is also associated with resistance to EGFR inhibitor in metastatic CRC patients. The BRAF V600E mutation is found in sporadic microsatellite unstable CRCs, and thus is helpful for ruling out Lynch syndrome. In addition, the KRAS mutation is a prognostic biomarker and the PIK3CA mutation is a molecular biomarker predicting response to phosphoinositide 3-kinase/AKT/mammalian target of rapamycin inhibitors and response to aspirin therapy in CRC patients. Additionally, HER2 testing should be performed in all recurrent or metastatic GCs. If the results of HER2 immunohistochemistry are equivocal, HER2 silver or fluorescence in situ hybridization testing are essential for confirmative determination of HER2 status. Epstein-Barr virus–positive GCs have distinct characteristics, including heavy lymphoid stroma, hypermethylation phenotype, and high expression of immune modulators. Recent advances in next-generation sequencing technologies enable us to examine various genetic alterations using a single test. Pathologists play a crucial role in ensuring reliable molecular testing and they should also take an integral role between molecular laboratories and clinicians.

  13. Gastrointestinal Bleeding Secondary to Calciphylaxis

    Science.gov (United States)

    Gupta, Nancy; Haq, Khwaja F.; Mahajan, Sugandhi; Nagpal, Prashant; Doshi, Bijal

    2015-01-01

    Patient: Female, 66 Final Diagnosis: Calciphylaxis Symptoms: Gastrointesinal haemorrhage Medication: None Clinical Procedure: Hemodialysis • blood transfusions Specialty: Gastroenterology and Hepatology Objective: Rare disease Background: Calciphylaxis is associated with a high mortality that approaches 80%. The diagnosis is usually made when obvious skin lesions (painful violaceous mottling of the skin) are present. However, visceral involvement is rare. We present a case of calciphylaxis leading to lower gastrointestinal (GI) bleeding and rectal ulceration of the GI mucosa. Case Report: A 66-year-old woman with past medical history of diabetes mellitus, hypertension, end-stage renal disease (ESRD), recently diagnosed ovarian cancer, and on hemodialysis (HD) presented with painful black necrotic eschar on both legs. The radiograph of the legs demonstrated extensive calcification of the lower extremity arteries. The hospital course was complicated with lower GI bleeding. A CT scan of the abdomen revealed severe circumferential calcification of the abdominal aorta, celiac artery, and superior and inferior mesenteric arteries and their branches. Colonoscopy revealed severe rectal necrosis. She was deemed to be a poor surgical candidate due to comorbidities and presence of extensive vascular calcifications. Recurrent episodes of profuse GI bleeding were managed conservatively with blood transfusion as needed. Following her diagnosis of calciphylaxis, supplementation with vitamin D and calcium containing phosphate binders was stopped. She was started on daily hemodialysis with low calcium dialysate bath as well as intravenous sodium thiosulphate. The clinical condition of the patient deteriorated. The patient died secondary to multiorgan failure. Conclusions: Calciphylaxis leading to intestinal ischemia/perforation should be considered in the differential diagnosis in ESRD on HD presenting with abdominal pain or GI bleeding. PMID:26572938

  14. Vitamin A absorption

    International Nuclear Information System (INIS)

    Baker, S.J.

    1976-01-01

    Investigation of the absorption of vitamin A and related substances is complicated by the multiplicity of forms in which they occur in the diet and by the possibility that they may be subject to different mechanisms of absorption. Present knowledge of these mechanisms is inadequate, especially in the case of carotenoids. Numerous tests of absorption have been developed. The most common has been the biochemical measurement of the rise in plasma vitamin A after an oral dose of retinol or retinyl ester, but standardization is inadequate. Radioisotope tests based upon assay of serum or faecal activity following oral administration of tritiated vitamin A derivaties hold considerable promise, but again standardization is inadequate. From investigations hitherto performed it is known that absorption of vitamin A is influenced by several diseases, although as yet the consistency of results and the correlation with other tests of intestinal function have often been poor. However, the test of vitamin A absorption is nevertheless of clinical importance as a specialized measure of intestinal function. (author)

  15. Food-dependent, exercise-induced gastrointestinal distress

    Directory of Open Access Journals (Sweden)

    Burini Roberto

    2011-09-01

    Full Text Available Abstract Among athletes strenuous exercise, dehydration and gastric emptying (GE delay are the main causes of gastrointestinal (GI complaints, whereas gut ischemia is the main cause of their nausea, vomiting, abdominal pain and (blood diarrhea. Additionally any factor that limits sweat evaporation, such as a hot and humid environment and/or body dehydration, has profound effects on muscle glycogen depletion and risk for heat illness. A serious underperfusion of the gut often leads to mucosal damage and enhanced permeability so as to hide blood loss, microbiota invasion (or endotoxemia and food-born allergen absorption (with anaphylaxis. The goal of exercise rehydration is to intake more fluid orally than what is being lost in sweat. Sports drinks provide the addition of sodium and carbohydrates to assist with intestinal absorption of water and muscle-glycogen replenishment, respectively. However GE is proportionally slowed by carbohydrate-rich (hyperosmolar solutions. On the other hand, in order to prevent hyponatremia, avoiding overhydration is recommended. Caregiver's responsibility would be to inform athletes about potential dangers of drinking too much water and also advise them to refrain from using hypertonic fluid replacements.

  16. 5-ALA/PpIX fluorescence detection of gastrointestinal neoplasia

    Science.gov (United States)

    Borisova, Ekaterina G.; Vladimirov, Borislav; Terziev, Ivan; Ivanova, Radina; Avramov, Latchezar

    2009-07-01

    In the recent study delta-ALA/PpIX is used as fluorescent marker for dysplasia and tumor detection in esophagus, stomach and colon. ALA is administered per os six to eight (depending on the lesion location) hours before measurements at dose 20mg/kg weight. High-power light-emitting diode at 405 nm is used as an excitation source. Special opto-mechanical device is built for the LED to use the light guide of standard video-endoscopic system. Through endoscopic instrumental channel a fiber is applied to return information about fluorescence to microspectrometer. The fluorescence detected from tumor sites has very complex spectral origins. It consists of autofluorescence, fluorescence from exogenous fluorophores and re-absorption from the chromophores accumulated in the tissue investigated. Spectral features observed during endoscopic investigations could be distinct as the next regions: 450-630 nm region, where tissue autofluorescence is observed; 630-710 nm region, where fluorescence of PpIX is clearly pronounced; 530-580 nm region, where minima in the autofluorescence signal are observed, related to re-absorption of oxy-hemoglobin in this spectral area. Endogenous and exogenous fluorescence spectra are used to develop simple but effective algorithm, based on dimensionless ratio of the signals at 560 and 635 nm, for differentiation of normal/abnormal gastrointestinal tissues. Very good correlation between fluorescence signals and histology examination of the lesions investigated is achieved.

  17. Restricted mass energy absorption coefficients for use in dosimetry

    International Nuclear Information System (INIS)

    Brahme, A.

    1977-02-01

    When matter is irradiated by a photon beam the fraction of energy absorbed locally in some region Rsub(Δ) (where the size of the region Rsub(Δ) is related to the range of secondary electrons of some restriction energy Δ) is expressed by the restricted mass energy absorption coefficient. In this paper an example is given of how restricted mass energy absorption coefficients can be calculated from existing differential photon interaction cross sections. Some applications of restricted mass absorption coefficients in dosimetry are also given. (B.D.)

  18. Fat absorption in germ-free and conventional rats artificially deprived of bile secretion

    OpenAIRE

    Demarne, Y.; Corring, T.; Pihet, A.; Sacquet, E.

    1982-01-01

    Bile duct ligation was performed in germ-free and conventional rats in order to study the effects of bile deprivation on the absorption of dietary lipids and the excretion of faecal lipids in the presence or the absence of gastrointestinal flora. The main consequence of bile duct ligation in conventional rats was decrease of about 50% in the apparent absorption of dietary lipids (peanut oil). In germ-free rats, absorption decreased by only about 25%.In conventional as well as in germ-free con...

  19. Effect of petroleum vapors inhalation on intestinal absorption of glucose and some amino acids in the rat

    International Nuclear Information System (INIS)

    Szablicka, E.; Oledzka, R.

    1989-01-01

    The proper intestinal absorption of nutrients, particularly sugars and amino acids, is necessary to keep the organism healthy. It is well known that various toxic compounds present in the environment can have an unfavorable influence. On the other hand it is also known that crude oil which pollutes the aqueous environment affects birds' gastrointestinal tract. Little is known about the influence of petroleum vapors on the gastrointestinal tract of animals and humans. The present study was undertaken to determine the effect of petroleum vapors inhalation on intestinal absorption of some nutrients (glucose, leucine, methionine) in rats

  20. Fractional Poisson process (II)

    International Nuclear Information System (INIS)

    Wang Xiaotian; Wen Zhixiong; Zhang Shiying

    2006-01-01

    In this paper, we propose a stochastic process W H (t)(H-bar (12,1)) which we call fractional Poisson process. The process W H (t) is self-similar in wide sense, displays long range dependence, and has more fatter tail than Gaussian process. In addition, it converges to fractional Brownian motion in distribution

  1. An Appetite for Fractions

    Science.gov (United States)

    Wilkerson, Trena L.; Bryan, Tommy; Curry, Jane

    2012-01-01

    This article describes how using candy bars as models gives sixth-grade students a taste for learning to represent fractions whose denominators are factors of twelve. Using paper models of the candy bars, students explored and compared fractions. They noticed fewer different representations for one-third than for one-half. The authors conclude…

  2. Can Kindergartners Do Fractions?

    Science.gov (United States)

    Cwikla, Julie

    2014-01-01

    Mathematics professor Julie Cwikla decided that she needed to investigate young children's understandings and see what precurricular partitioning notions young minds bring to the fraction table. Cwikla realized that only a handful of studies have examined how preschool-age and early elementary school-age students solve fraction problems (Empson…

  3. Absorption and distribution of 3H in horned cattle of different age

    International Nuclear Information System (INIS)

    Sirotkin, A.N.; Rusakov, N.V.

    1979-01-01

    Studied are the regularity of absorption of the tritium oxide in the gastrointestinal tract, the character of the distribution among the organs and of the radionuclide accumulation in horned cattle of different are. To determine the tritium absorption in the gastrointestinal tract the method of single oral and intravenous injection of radionuclide were used. The tritium concentration values in organs and tissues of horned cattle are presented. The results obtained show that tritium distribution in the organism occurs uniformly and does not depend on the way of intake. With the age the tritium concentration in dry residue increases and in the water phase decreases. The tritium absorption value calculated in the digestive tract of the horned cattle practically does not depend on the animals' age and constitutes 96.2% in average

  4. Patient health communication mediating effects between gastrointestinal symptoms and gastrointestinal worry in pediatric inflammatory bowel disease

    Science.gov (United States)

    To investigate the effects of patient health communication regarding their inflammatory bowel disease (IBD) to their health care providers and significant others in their daily life as a mediator in the relationship between gastrointestinal symptoms and gastrointestinal worry in pediatric patients. ...

  5. European Society of Gastrointestinal Endoscopy - Establishing the key unanswered research questions within gastrointestinal endoscopy

    DEFF Research Database (Denmark)

    Rees, Colin J; Ngu, Wee Sing; Regula, Jaroslaw

    2016-01-01

    Background and study aim: Gastrointestinal endoscopy is a rapidly evolving research field. The European Society of Gastrointestinal Endoscopy (ESGE) plays a key role in shaping opinion and endoscopy activity throughout Europe and further afield. Establishing key unanswered questions within the fi...

  6. Fractional bosonic strings

    Science.gov (United States)

    Diaz, Victor Alfonzo; Giusti, Andrea

    2018-03-01

    The aim of this paper is to present a simple generalization of bosonic string theory in the framework of the theory of fractional variational problems. Specifically, we present a fractional extension of the Polyakov action, for which we compute the general form of the equations of motion and discuss the connection between the new fractional action and a generalization the Nambu-Goto action. Consequently, we analyze the symmetries of the modified Polyakov action and try to fix the gauge, following the classical procedures. Then we solve the equations of motion in a simplified setting. Finally, we present a Hamiltonian description of the classical fractional bosonic string and introduce the fractional light-cone gauge. It is important to remark that, throughout the whole paper, we thoroughly discuss how to recover the known results as an "integer" limit of the presented model.

  7. Monitoring and treatment of acute gastrointestinal bleeding.

    Science.gov (United States)

    Lenjani, Basri; Zeka, Sadik; Krasniqi, Salih; Bunjaku, Ilaz; Jakupi, Arianit; Elshani, Besni; Xhafa, Agim

    2012-01-01

    Acute gastrointestinal bleeding-massive acute bleeding from gastrointestinal section is one of the most frequent forms of acute abdomen. The mortality degree in emergency surgery is about 10%. It's very difficult to identify the place of bleeding and etiology. The important purpose of this research is to present the cases of acute gastrointestinal bleeding from the patients which were monitored and treated at The University Clinical Center of Kosova-Emergency Center in Pristina. These inquests included 137 patients with acute gastrointestinal bleeding who were treated in emergency center of The University Clinical Center in Pristina for the period from January 2005 until December 2006. From 137 patients with acute gastrointestinal bleeding 41% or 29% was female and 96% or 70.1% male. Following the sex we gained a high significant difference of statistics (p < 0.01). The gastrointestinal bleeding was two times more frequent in male than in female. Also in the age-group we had a high significant difference of statistics (p < 0.01) 63.5% of patients were over 55 years old. The mean age of patients with an acute gastrointestinal bleeding was 58.4 years SD 15.8 age. The mean age for female patients was 56.4 age SD 18.5 age. The patients with arterial systolic pressure under 100 mmHg have been classified as patients with hypovolemic shock. They participate with 17.5% in all prevalence of acute gastrointestinal bleeding. From the number of prevalence 2 {1.5%} patients have been diagnosed with peptic ulcer, 1 {0.7%} as gastric perforation and 1 {0.7%} with intestine ischemia. Abdominal Surgery and Intensive Care 2 or 1.5% died, 1 at intensive care unit and 1 at nephrology. As we know the severe condition of the patients with gastrointestinal bleeding and etiology it is very difficult to establish, we need to improve for the better conditions in our emergency center for treatment and initiation base of clinic criteria.

  8. Neutron resonance absorption theory

    International Nuclear Information System (INIS)

    Reuss, P.

    1991-11-01

    After some recalls on the physics of neutron resonance absorption during their slowing down, this paper presents the main features of the theoretical developments performed by the french school of reactor physics: the effective reaction rate method so called Livolant-Jeanpierre theory, the generalizations carried out by the author, and the probability table method [fr

  9. Noble gas absorption process

    International Nuclear Information System (INIS)

    Thomas, J.W.

    1975-01-01

    A method of removing a noble gas from air comprising the use of activated carbon filters in stages in which absorption and desorption steps in succession are conducted in order to increase the capacity of the filters is described. (U.S.)

  10. Total photon absorption

    International Nuclear Information System (INIS)

    Carlos, P.

    1985-01-01

    Experimental methods using real photon beams for measurements of total photonuclear absorption cross section σ(Tot : E/sub γ/) are recalled. Most recent σ(Tot : E/sub γ/)results for complex nuclei and in the nucleon resonance region are presented

  11. Chemical Absorption Materials

    DEFF Research Database (Denmark)

    Thomsen, Kaj

    2011-01-01

    Chemical absorption materials that potentially can be used for post combustion carbon dioxide capture are discussed. They fall into five groups, alkanolamines, alkali carbonates, ammonia, amino acid salts, and ionic liquids. The chemistry of the materials is discussed and advantages and drawbacks...

  12. Upper gastrointestinal symptoms in autoimmune gastritis

    Science.gov (United States)

    Carabotti, Marilia; Lahner, Edith; Esposito, Gianluca; Sacchi, Maria Carlotta; Severi, Carola; Annibale, Bruno

    2017-01-01

    Abstract Autoimmune gastritis is often suspected for its hematologic findings, and rarely the diagnosis is made for the presence of gastrointestinal symptoms. Aims of this cross-sectional study were to assess in a large cohort of patients affected by autoimmune gastritis the occurrence and the pattern of gastrointestinal symptoms and to evaluate whether symptomatic patients are characterized by specific clinical features. Gastrointestinal symptoms of 379 consecutive autoimmune gastritis patients were systematically assessed and classified following Rome III Criteria. Association between symptoms and anemia pattern, positivity to gastric autoantibodies, Helicobacter pylori infection, and concomitant autoimmune disease were evaluated. In total, 70.2% of patients were female, median age 55 years (range 17–83). Pernicious anemia (53.6%), iron deficiency anemia (34.8%), gastric autoantibodies (68.8%), and autoimmune disorders (41.7%) were present. However, 56.7% of patients complained of gastrointestinal symptoms, 69.8% of them had exclusively upper symptoms, 15.8% only lower and 14.4% concomitant upper and lower symptoms. Dyspepsia, subtype postprandial distress syndrome was the most represented, being present in 60.2% of symptomatic patients. Univariate and multivariate analyses showed that age gastritis is associated in almost 60% of cases with gastrointestinal symptoms, in particular dyspepsia. Dyspepsia is strictly related to younger age, no smoking, and absence of anemia. PMID:28072728

  13. Connecting gastrointestinal cancer risk to cadmium and lead exposure in the Chaoshan population of Southeast China.

    Science.gov (United States)

    Lin, Xueqiong; Peng, Lin; Xu, Xijin; Chen, Yanrong; Zhang, Yuling; Huo, Xia

    2018-04-17

    Cadmium (Cd) and lead (Pb) pose a serious threat to human health because of its carcinogenicity. China ranks first according to the Global Cancer Report for 2014 in newly diagnosed gastrointestinal cancers and cancer deaths. The aim of the present study was to evaluate the association of Cd and Pb burden with the risk of gastrointestinal cancers in a hospital-based case-control study from southern regions of China, Chaoshan area. A total of 279 hospitalized patients were recruited in this study, of which 167 were gastrointestinal cancer cases (70 esophageal cancer, 51 gastric cancer, and 46 colorectal cancer), and 112 controls were recruited from two hospitals in the Chaoshan area of southeast China. Basic clinical data and information on gender, age, and other demographic characteristics were collected from medical records. Blood Cd and Pb levels were detected by graphite furnace atomizer absorption spectrophotometry (GFAAS). Blood Cd/Pb levels and over-limit ratios between cases and controls were compared by Mann-Whitney U and Kruskal-Wallis H tests. We used logistic regression to estimate odds ratios (ORs) as measures of relative risk and explored the relationships between blood Cd/Pb levels and gastrointestinal cancer risk and clinicopathological characteristics. Median levels of blood Cd and Pb in cases (2.12 and 60.03 μg/L, respectively) were significantly higher than those of controls (1.47 and 53.84 μg/L, respectively). The over-limit ratios for Cd (≥ 5 μg/L) and Pb (≥ 100 μg/L) in the cases were both higher than that of controls. Blood Cd levels had a tendency to accumulate in the human body with gender, age, and tobacco smoking, while blood Pb levels only were associated with tobacco smoking. The logistic regression model illustrated that gastrointestinal cancers were significantly associated with blood Cd levels and blood Pb levels. The concentrations of Cd and Pb in patients with T3 + T4 stage were markedly higher than in patients

  14. Fractional Order Generalized Information

    Directory of Open Access Journals (Sweden)

    José Tenreiro Machado

    2014-04-01

    Full Text Available This paper formulates a novel expression for entropy inspired in the properties of Fractional Calculus. The characteristics of the generalized fractional entropy are tested both in standard probability distributions and real world data series. The results reveal that tuning the fractional order allow an high sensitivity to the signal evolution, which is useful in describing the dynamics of complex systems. The concepts are also extended to relative distances and tested with several sets of data, confirming the goodness of the generalization.

  15. Fractional finite Fourier transform.

    Science.gov (United States)

    Khare, Kedar; George, Nicholas

    2004-07-01

    We show that a fractional version of the finite Fourier transform may be defined by using prolate spheroidal wave functions of order zero. The transform is linear and additive in its index and asymptotically goes over to Namias's definition of the fractional Fourier transform. As a special case of this definition, it is shown that the finite Fourier transform may be inverted by using information over a finite range of frequencies in Fourier space, the inversion being sensitive to noise. Numerical illustrations for both forward (fractional) and inverse finite transforms are provided.

  16. Social Trust and Fractionalization:

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    2008-01-01

    This paper takes a closer look at the importance of fractionalization for the creation of social trust. It first argues that the determinants of trust can be divided into two categories: those affecting individuals' trust radii and those affecting social polarization. A series of estimates using...... a much larger country sample than in previous literature confirms that fractionalization in the form of income inequality and political diversity adversely affects social trust while ethnic diversity does not. However, these effects differ systematically across countries, questioning standard...... interpretations of the influence of fractionalization on trust....

  17. New advances in gastrointestinal motility research

    CERN Document Server

    Pullan, A; Farrugia, G

    2013-01-01

    Research into gastrointestinal motility has received renewed interest in part due to recent advances in the techniques for measuring the structure and function of gastrointestinal cells, tissue and organs. The integration of this wealth of data into biophysically based computation models can aid in interpretation of experimental and clinical measurements and the refinement of measurement techniques. The contents of this book span multiple scales - from cell, tissue, organ, to whole body and is divided into four broad sections covering: i) gastrointestinal cellular activity and tissue structure; (ii) techniques for measuring, analyzing and visualizing high-resolution extra-cellular recordings; (iii) methods for sensing gastroelectrical activity using non-invasive bio-electro-magnetic fields and for modulating the underlying gastric electrical activity, and finally; (iv) methods for assessing manometric and videographic motility patterns and the application of these data for predicting the flow and mixing behav...

  18. The chronic gastrointestinal manifestations of Chagas disease

    Directory of Open Access Journals (Sweden)

    Nilce Mitiko Matsuda

    2009-01-01

    Full Text Available Chagas disease is an infectious disease caused by the protozoan Trypanosoma cruzi. The disease mainly affects the nervous system, digestive system and heart. The objective of this review is to revise the literature and summarize the main chronic gastrointestinal manifestations of Chagas disease. The chronic gastrointestinal manifestations of Chagas disease are mainly a result of enteric nervous system impairment caused by T. cruzi infection. The anatomical locations most commonly described to be affected by Chagas disease are salivary glands, esophagus, lower esophageal sphincter, stomach, small intestine, colon, gallbladder and biliary tree. Chagas disease has also been studied in association with Helicobacter pylori infection, interstitial cells of Cajal and the incidence of gastrointestinal cancer.

  19. Transfusion strategy for acute upper gastrointestinal bleeding.

    Science.gov (United States)

    Handel, James; Lang, Eddy

    2015-09-01

    Clinical question Does a hemoglobin transfusion threshold of 70 g/L yield better patient outcomes than a threshold of 90 g/L in patients with acute upper gastrointestinal bleeding? Article chosen Villanueva C, Colomo A, Bosch A, et al. Transfusion strategies for acute upper gastrointestinal bleeding. N Engl J Med 2013;368(1):11-21. Study objectives The authors of this study measured mortality, from any cause, within the first 45 days, in patients with acute upper gastrointestinal bleeding, who were managed with a hemoglobin threshold for red cell transfusion of either 70 g/L or 90 g/L. The secondary outcome measures included rate of further bleeding and rate of adverse events.

  20. Bayesian network modelling of upper gastrointestinal bleeding

    Science.gov (United States)

    Aisha, Nazziwa; Shohaimi, Shamarina; Adam, Mohd Bakri

    2013-09-01

    Bayesian networks are graphical probabilistic models that represent causal and other relationships between domain variables. In the context of medical decision making, these models have been explored to help in medical diagnosis and prognosis. In this paper, we discuss the Bayesian network formalism in building medical support systems and we learn a tree augmented naive Bayes Network (TAN) from gastrointestinal bleeding data. The accuracy of the TAN in classifying the source of gastrointestinal bleeding into upper or lower source is obtained. The TAN achieves a high classification accuracy of 86% and an area under curve of 92%. A sensitivity analysis of the model shows relatively high levels of entropy reduction for color of the stool, history of gastrointestinal bleeding, consistency and the ratio of blood urea nitrogen to creatinine. The TAN facilitates the identification of the source of GIB and requires further validation.

  1. FRACTIONS: CONCEPTUAL AND DIDACTIC ASPECTS

    Directory of Open Access Journals (Sweden)

    Sead Rešić

    2016-09-01

    Full Text Available Fractions represent the manner of writing parts of whole numbers (integers. Rules for operations with fractions differ from rules for operations with integers. Students face difficulties in understanding fractions, especially operations with fractions. These difficulties are well known in didactics of Mathematics throughout the world and there is a lot of research regarding problems in learning about fractions. Methods for facilitating understanding fractions have been discovered, which are essentially related to visualizing operations with fractions.

  2. Fractional Stochastic Field Theory

    Science.gov (United States)

    Honkonen, Juha

    2018-02-01

    Models describing evolution of physical, chemical, biological, social and financial processes are often formulated as differential equations with the understanding that they are large-scale equations for averages of quantities describing intrinsically random processes. Explicit account of randomness may lead to significant changes in the asymptotic behaviour (anomalous scaling) in such models especially in low spatial dimensions, which in many cases may be captured with the use of the renormalization group. Anomalous scaling and memory effects may also be introduced with the use of fractional derivatives and fractional noise. Construction of renormalized stochastic field theory with fractional derivatives and fractional noise in the underlying stochastic differential equations and master equations and the interplay between fluctuation-induced and built-in anomalous scaling behaviour is reviewed and discussed.

  3. Discrete fractional calculus

    CERN Document Server

    Goodrich, Christopher

    2015-01-01

    This text provides the first comprehensive treatment of the discrete fractional calculus. Experienced researchers will find the text useful as a reference for discrete fractional calculus and topics of current interest. Students who are interested in learning about discrete fractional calculus will find this text to provide a useful starting point. Several exercises are offered at the end of each chapter and select answers have been provided at the end of the book. The presentation of the content is designed to give ample flexibility for potential use in a myriad of courses and for independent study. The novel approach taken by the authors includes a simultaneous treatment of the fractional- and integer-order difference calculus (on a variety of time scales, including both the usual forward and backwards difference operators). The reader will acquire a solid foundation in the classical topics of the discrete calculus while being introduced to exciting recent developments, bringing them to the frontiers of the...

  4. Fractional smith chart theory

    KAUST Repository

    Shamim, Atif; Radwan, Ahmed Gomaa; Salama, Khaled N.

    2011-01-01

    matching networks, where the fractional approach proves to be much more versatile and results in a single element matching network for a complex load as compared to the two elements in the conventional approach. © 2010 IEEE.

  5. Peculiarities of determination of coefficient of radionuclide absorption in alimentary canal of ruminants

    International Nuclear Information System (INIS)

    Korneev, N.A.; Sirotkin, A.N.; Rasin, I.M.; Sarapul'tsev, I.A.; Abramova, T.N.

    1986-01-01

    Sheep taken as example, the new method for calculation of the coefficient of radionuclide ( 65 Zn) absorption in gastrointestinal tract (GIT) is suggested. It is shown that the radionuclide absorption process of sheep lasted 35 h. In case of parenteral intake radionuclide excretion from tissues and organs and its inclusion in structural parts of blood occurs. In animals to which 65 Zn is injected orally, the same processes at 65 Zn simultaneous absorption in GIT during 35 h take place. In 35 hours after radio nuclide injection its absorption coefficient in the GIT of sheep constituted 10.1+-0.05%. Using traditional calculation methods the 65 Zn absorption coefficient for the first 24 h constituted 6.6%

  6. Eastern Canadian Gastrointestinal Cancer Consensus Conference 2016.

    Science.gov (United States)

    Bossé, D; Ng, T; Ahmad, C; Alfakeeh, A; Alruzug, I; Biagi, J; Brierley, J; Chaudhury, P; Cleary, S; Colwell, B; Cripps, C; Dawson, L A; Dorreen, M; Ferland, E; Galiatsatos, P; Girard, S; Gray, S; Halwani, F; Kopek, N; Mahmud, A; Martel, G; Robillard, L; Samson, B; Seal, M; Siddiqui, J; Sideris, L; Snow, S; Thirwell, M; Vickers, M; Goodwin, R; Goel, R; Hsu, T; Tsvetkova, E; Ward, B; Asmis, T

    2016-12-01

    The annual Eastern Canadian Gastrointestinal Cancer Consensus Conference 2016 was held in Montreal, Quebec, 5-7 February. Experts in radiation oncology, medical oncology, surgical oncology, and infectious diseases involved in the management of patients with gastrointestinal malignancies participated in presentations and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses multiple topics: ■ Follow-up and survivorship of patients with resected colorectal cancer■ Indications for liver metastasectomy■ Treatment of oligometastases by stereotactic body radiation therapy■ Treatment of borderline resectable and unresectable pancreatic cancer■ Transarterial chemoembolization in hepatocellular carcinoma■ Infectious complications of antineoplastic agents.

  7. Congenital diaphragmatic hernia with gastrointestinal symptomatology

    International Nuclear Information System (INIS)

    Siroka, M.; Bilicky, J.; Hernesniemi, B.

    2014-01-01

    The authors report a case of 6-week-old baby boy with congenital diaphragmatic hernia(CDH). He presented with nonspecific gastrointestinal symptoms. CDH is commonly manifested by nonspecific respiratory problems. The symptoms of CDH in older infants are atypical and misleading. Children may have only gastrointestinal problems even the acute abdomen. In our case, the ultrasound examination of abdomen did not detect the exact cause of vomiting and intolerance of oral intake, but the explanation has brought classic chest X-ray. (author)

  8. Gastrointestinal complications of leukemia and its treatment

    International Nuclear Information System (INIS)

    Hunter, T.B.; Bjelland, J.C.

    1984-01-01

    Leukemia represents 4% of all cancer deaths and is the leading cause of death from malignancy for all patients under 30 years of age. Various rare, usually preterminal gastrointestinal complications of leukemia have been reported. These complications are becoming more common and no longer should be considered unusual. Their increasing incidence is the result of new, more aggressive treatment methods and increased patient lifespan. The authors describe the relative incidence and common radiographic presentations of leukemia-related gastrointestinal disease and emphasize that its prognosis is favorable with prompt diagnosis and treatment

  9. Gastrointestinal hormone research - with a Scandinavian annotation

    DEFF Research Database (Denmark)

    Rehfeld, Jens F

    2015-01-01

    Gastrointestinal hormones are peptides released from neuroendocrine cells in the digestive tract. More than 30 hormone genes are currently known to be expressed in the gut, which makes it the largest hormone-producing organ in the body. Modern biology makes it feasible to conceive the hormones...... as a blood-borne hormone, a neurotransmitter, a local growth factor or a fertility factor. The targets of gastrointestinal hormones are specific G-protein-coupled receptors that are expressed in the cell membranes also outside the digestive tract. Thus, gut hormones not only regulate digestive functions...

  10. Diagnosis of liver, biliary tract and gastrointestine

    International Nuclear Information System (INIS)

    Aburano, Tamio

    1981-01-01

    The role of RI imaging in the diagnosis of lesions of the liver, biliary tracts and gastrointestinal tracts are reviewed, and representative cases are shown. Liver scintigraphy was of value for the diagnosis of lesions limitted to the liver such as primary and metastatic liver cancer and inflammatory liver diseases. However, RI methods were less useful in the diagnosis of lesions of the biliary tracts and stomach. RI scintigraphy was more sensitive than angiography in the detection of Meckel's deverticulum, Ballet's esophagus, and gastrointestinal hemorrhage. (Tsunoda, M.)

  11. Multiple Gastrointestinal Complications of Crack Cocaine Abuse

    Directory of Open Access Journals (Sweden)

    Neal Carlin

    2014-01-01

    Full Text Available Cocaine and its alkaloid free base “crack-cocaine” have long since been substances of abuse. Drug abuse of cocaine via oral, inhalation, intravenous, and intranasal intake has famously been associated with a number of medical complications. Intestinal ischemia and perforation remain the most common manifestations of cocaine associated gastrointestinal disease and have historically been associated with oral intake of cocaine. Here we find a rare case of two relatively uncommon gastrointestinal complications of hemorrhage and pancreatitis presenting within a single admission in a chronic crack cocaine abuser.

  12. Upper gastrointestinal bleeding - state of the art.

    Science.gov (United States)

    Szura, Mirosław; Pasternak, Artur

    2014-01-01

    Upper gastrointestinal (GI) bleeding is a condition requiring immediate medical intervention, with high associated mortality exceeding 10%. The most common cause of upper GI bleeding is peptic ulcer disease, which largely corresponds to the intake of NSAIDs and Helicobacter pylori infection. Endoscopy is the essential tool for the diagnosis and treatment of active upper GI hemorrhage. Endoscopic therapy together with proton pump inhibitors and eradication of Helicobacter pylori significantly reduces rebleeding rates, mortality and number of emergency surgical interventions. This paper presents contemporary data on the diagnosis and treatment of upper gastrointestinal bleeding.

  13. Scintigraphic demonstration of acute gastrointestinal bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Alavi, A.

    1980-01-01

    Acute gastrointestinal bleeding may be localized using noninvasive radionuclide methods. We have favored the use of technetium-99m sulfur colloid with sequential imaging because of the rapid clearance of background activity. Definition of the site of upper gastrointestinal bleeding, however, may be obscured by intense uptake of radioactivity by liver and spleen. The sensitivity of the method is such that the bleeding rates of 0.05-0.1 ml/min can be detected compared to a sensitivity of 0.5 ml/min for angiography.

  14. Wnt Signalling in Gastrointestinal Epithelial Stem Cells

    Directory of Open Access Journals (Sweden)

    Dustin J. Flanagan

    2018-03-01

    Full Text Available Wnt signalling regulates several cellular functions including proliferation, differentiation, apoptosis and migration, and is critical for embryonic development. Stem cells are defined by their ability for self-renewal and the ability to be able to give rise to differentiated progeny. Consequently, they are essential for the homeostasis of many organs including the gastrointestinal tract. This review will describe the huge advances in our understanding of how stem cell functions in the gastrointestinal tract are regulated by Wnt signalling, including how deregulated Wnt signalling can hijack these functions to transform cells and lead to cancer.

  15. Granular cells Tumor in the gastrointestinal tract

    International Nuclear Information System (INIS)

    Castano LL, Rodrigo; Gaitan B, Maria H; Juliao E, Fabian

    2005-01-01

    Granular cells tumors are ubiquitous lesions in the gastrointestinal tract, are rare and asymptomatic and they are generally an incidental discovery at gastroduodenoscopy or colonoscopy. In the gastrointestinal tract they are more frequently located in the esophagus, right colon and rectum, stomach, appendix, small intestine or biliopancreatic tract. This article describes three patients with four tumors of granular cells in rectum, esophagus (2 lesions) and appendix. It becomes special emphasis in their neural origin, their benign behavior that justifies the endoscopic resections or limited surgical excisions and the necessity of a pursuit for the possibility, although little, of malignant transformation

  16. Intracellular Cadmium Isotope Fractionation

    Science.gov (United States)

    Horner, T. J.; Lee, R. B.; Henderson, G. M.; Rickaby, R. E.

    2011-12-01

    Recent stable isotope studies into the biological utilization of transition metals (e.g. Cu, Fe, Zn, Cd) suggest several stepwise cellular processes can fractionate isotopes in both culture and nature. However, the determination of fractionation factors is often unsatisfactory, as significant variability can exist - even between different organisms with the same cellular functions. Thus, it has not been possible to adequately understand the source and mechanisms of metal isotopic fractionation. In order to address this problem, we investigated the biological fractionation of Cd isotopes within genetically-modified bacteria (E. coli). There is currently only one known biological use or requirement of Cd, a Cd/Zn carbonic anhydrase (CdCA, from the marine diatom T. weissfloggii), which we introduce into the E. coli genome. We have also developed a cleaning procedure that allows for the treating of bacteria so as to study the isotopic composition of different cellular components. We find that whole cells always exhibit a preference for uptake of the lighter isotopes of Cd. Notably, whole cells appear to have a similar Cd isotopic composition regardless of the expression of CdCA within the E. coli. However, isotopic fractionation can occur within the genetically modified E. coli during Cd use, such that Cd bound in CdCA can display a distinct isotopic composition compared to the cell as a whole. Thus, the externally observed fractionation is independent of the internal uses of Cd, with the largest Cd isotope fractionation occurring during cross-membrane transport. A general implication of these experiments is that trace metal isotopic fractionation most likely reflects metal transport into biological cells (either actively or passively), rather than relating to expression of specific physiological function and genetic expression of different metalloenzymes.

  17. The potential of immobilized artificial membrane chromatography to predict human oral absorption.

    Science.gov (United States)

    Tsopelas, Fotios; Vallianatou, Theodosia; Tsantili-Kakoulidou, Anna

    2016-01-01

    The potential of immobilized artificial membrane (IAM) chromatography to estimate human oral absorption (%HOA) was investigated. For this purpose, retention indices on IAM stationary phases reported previously by our group or measured by other authors under similar conditions were used to model %HOA data, compiled from literature sources. Considering the pH gradient in gastrointestinal tract, the highest logkw(IAM) values were considered, obtained either at pH7.4 or 5.5, defined as logkw(IAM)(best). Non linear models were established upon introduction of additional parameters and after exclusion of drugs which are substrates either to efflux or uptake transporters. The best model included Abraham's hydrogen-bond acidity parameter, molecular weight as well as the positively and negatively charged molecular fractions. For reasons of comparison between IAM chromatography and traditional lipophilicity, corresponding models were derived by replacing IAM retention factors with octanol-water distribution coefficients (logD). An overexpression of electrostatic interactions with phosphate anions was observed in the case of IAM retention as expressed by the negative contribution of the positively charged fraction F(+). The same parameter is statistically significant also in the logD model, but with a positive sign, indicating the attraction of basic drugs in the negatively charged inner membrane. To validate the obtained models a blind test set of 22 structurally diverse drugs was used, whose logkw(IAM)(best) values were determined and analyzed in the present study under similar conditions. IAM retention factors were further compared with MDCK cell lines permeability data taken from literature for a set of validation drugs. The overexpression of electrostatic interactions with phosphate anions on IAM surface was also evident in respect to MDCK permeability. In contrast to the clear classification between drugs with high and poor (or intermediate) absorption provided by MDCK

  18. Fractional laser skin resurfacing.

    Science.gov (United States)

    Alexiades-Armenakas, Macrene R; Dover, Jeffrey S; Arndt, Kenneth A

    2012-11-01

    Laser skin resurfacing (LSR) has evolved over the past 2 decades from traditional ablative to fractional nonablative and fractional ablative resurfacing. Traditional ablative LSR was highly effective in reducing rhytides, photoaging, and acne scarring but was associated with significant side effects and complications. In contrast, nonablative LSR was very safe but failed to deliver consistent clinical improvement. Fractional LSR has achieved the middle ground; it combined the efficacy of traditional LSR with the safety of nonablative modalities. The first fractional laser was a nonablative erbium-doped yttrium aluminum garnet (Er:YAG) laser that produced microscopic columns of thermal injury in the epidermis and upper dermis. Heralding an entirely new concept of laser energy delivery, it delivered the laser beam in microarrays. It resulted in microscopic columns of treated tissue and intervening areas of untreated skin, which yielded rapid reepithelialization. Fractional delivery was quickly applied to ablative wavelengths such as carbon dioxide, Er:YAG, and yttrium scandium gallium garnet (2,790 nm), providing more significant clinical outcomes. Adjustable laser parameters, including power, pitch, dwell time, and spot density, allowed for precise determination of percent surface area, affected penetration depth, and clinical recovery time and efficacy. Fractional LSR has been a significant advance to the laser field, striking the balance between safety and efficacy.

  19. Cosmological Evolution of QSO Absorption Systems

    Science.gov (United States)

    Stengler-Larrea, Erik

    1995-08-01

    First, the evolution with cosmic time of the hydrogen clouds which produce the Lyman-alpha absorption lines is studied in dependence on the strength of these lines. From the analysis it is concluded that the results show no evidence of a dependence in the sense of stronger lines evolving faster, although for the resolution at which the used observations were done, it can not be ruled out. Within the same analysis, a distribution of the Doppler parameter of the lines was obtained, with large values and a wide spread. This parameter being an indicator of the gas temperature, this result is in accordance with high temperatures and, consequently, large ionised fractions and a large fraction of the baryonic matter of the universe being associated with these clouds. However, recent high resolution studies seem to reveal that much lower temperatures are characteristic of the clouds. The main content of this thesis, however, focuses on the redshift evolution of the absorbing systems producing absorption at the Lyman limit and of the amount of CIV producing CIV absorption lines. Regarding the CIV absorbers, previous predictions on the effects underlying their redshift distribution pointed to an increase with redshift of the absorbing column densities. In this thesis the first direct measurements of such column densities by profile fitting of a large number of absorption systems (73) are presented, confirming the predictions of a decrease of at least a factor of 3 between z=1.5 and z=3.0. The study on the evolution of Lyman limit absorption systems (LLSs) puts an end to previous discrepancies between the results of different groups. Both a smooth single power law dependence of the LLS number density on redshift indicating no evolution in number density for 0.4 Team of the HST Key Project on QSO absorption lines, and in particular to estimate the necessary exposure times, the magnitudes of several of these objects had to be re-measured. The acquisition of their images and the

  20. Linear absorptive dielectrics

    Science.gov (United States)

    Tip, A.

    1998-06-01

    Starting from Maxwell's equations for a linear, nonconducting, absorptive, and dispersive medium, characterized by the constitutive equations D(x,t)=ɛ1(x)E(x,t)+∫t-∞dsχ(x,t-s)E(x,s) and H(x,t)=B(x,t), a unitary time evolution and canonical formalism is obtained. Given the complex, coordinate, and frequency-dependent, electric permeability ɛ(x,ω), no further assumptions are made. The procedure leads to a proper definition of band gaps in the periodic case and a new continuity equation for energy flow. An S-matrix formalism for scattering from lossy objects is presented in full detail. A quantized version of the formalism is derived and applied to the generation of Čerenkov and transition radiation as well as atomic decay. The last case suggests a useful generalization of the density of states to the absorptive situation.

  1. Oral adverse effects of gastrointestinal drugs and considerations for dental management in patients with gastrointestinal disorders

    Directory of Open Access Journals (Sweden)

    Ramya Karthik

    2012-01-01

    Full Text Available Gastrointestinal disease is associated with alterations in the mouth or influence the course of the dental diseases, and the dental health care workers are expected to recognize, diagnose, and treat oral conditions associated with gastrointestinal diseases and also provide safe and appropriate dental care for afflicted individuals. Drugs used in the management of these diseases result in oral adverse effects and also are known to interact with those prescribed during dental care. Hence, this article has reviewed the drug considerations and guidelines for drug use during dental management of patients with gastrointestinal diseases.

  2. Iron absorption studies

    International Nuclear Information System (INIS)

    Ekenved, G.

    1976-01-01

    The main objective of the present work was to study iron absorption from different iron preparations in different types of subjects and under varying therapeutic conditions. The studies were performed with different radioiron isotope techniques and with a serum iron technique. The preparations used were solutions of ferrous sulphate and rapidly-disintegrating tablets containing ferrous sulphate, ferrous fumarate and ferrous carbonate and a slow-release ferrous sulphate tablet of an insoluble matrix type (Duroferon Durules). The serum iron method was evaluated and good correlation was found between the serum iron response and the total amount of iron absorbed after an oral dose of iron given in solution or in tablet form. New technique for studying the in-vivo release properties of tablets was presented. Iron tablets labelled with a radio-isotope were given to healthy subjects. The decline of the radioactivity in the tablets was followed by a profile scanning technique applied to different types of iron tablets. The release of iron from the two types of tablets was shown to be slower in vivo than in vitro. It was found that co-administration of antacids and iron tablets led to a marked reduction in the iron absorption and that these drugs should not be administered sumultaneously. A standardized meal markedly decreased the absorbability of iron from iron tablets. The influence of the meal was more marked with rapidly-disintegrating than with slow-release ferrous sulphate tablets. The absorption from rapidly-disintegrating and slow-release ferrous sulphate tablets was compared under practical clinical conditions during an extended treatment period. The studies were performed in healthy subjects, blood donors and patients with iron deficiency anaemia and it was found that the absorption of iron from the slow-release tablets was significantly better than from the rapidly-disintegrating tablets in all three groups of subjects. (author)

  3. Gamma absorption meter

    International Nuclear Information System (INIS)

    Dincklage, R.D. von.

    1984-01-01

    The absorption meter consists of a radiation source, a trough for the absorbing liquid and a detector. It is characterized by the fact that there is a foil between the detector and the trough, made of a material whose binding energy of the K electrons is a little greater than the energy of the photons emitted by the radiation source. The source of radiation and foil are replaceable. (orig./HP) [de

  4. Total Absorption Spectroscopy

    International Nuclear Information System (INIS)

    Rubio, B.; Gelletly, W.

    2007-01-01

    The problem of determining the distribution of beta decay strength (B(GT)) as a function of excitation energy in the daughter nucleus is discussed. Total Absorption Spectroscopy is shown to provide a way of determining the B(GT) precisely. A brief history of such measurements and a discussion of the advantages and disadvantages of this technique, is followed by examples of two recent studies using the technique. (authors)

  5. Absorption and long term retention of Mn-54 in man

    International Nuclear Information System (INIS)

    Cederblad, A.; Eriksson, R.; Alpsten, M.; Davidsson, L.

    1989-01-01

    The manganese absorption is found to be ≤ 16% after administration of some infant diets as well as from water solutions of manganese. These absorption figures might in some cases be an underestimation of the true initial absorption due to the rapid initial excretion of Mn-54. This means that both the often quoted figure for manganese absorption in humans, 3.0±0.5% and the value 10% used by ICRP 1979 are underestimations of the fractional absorption of manganese under some circumstances. The long term retention curve obtained, where the ratio between retention day 200 and day 30 had a mean value of 0.19 (range 0.10-0.35), could be compared to the two-component exponential function used by ICRP 1979 based on studies by Mahoney and Small 1968 where the corresponding ratio is 0.045. In the study by Mahoney and Small Mn-54 retention was studied after intravenous administration. We have earlier observed a difference between the metabolic handling of Mn-54 introduced orally and intravenously in man. Another model proposed by Caughtrey and Thorne 1983 consisting of a three component exponential function is in better agreement with our measurements and gives the ratio 0.22. The ICRP model for dose calculations tends to underestimate fractional absorption as well as long term retention of manganese. (orig./HP)

  6. Comparison of the effect of sorbitol and glucose on calcium absorption in postmenopausal women

    International Nuclear Information System (INIS)

    Francis, R.M.; Peacock, M.; Barkworth, S.A.; Marshall, D.H.

    1986-01-01

    It has been suggested that the oral administration of sorbitol promotes calcium absorption, while glucose has no effect. We have therefore compared the effect of oral sorbitol and glucose on the absorption of radiocalcium from low and high carrier loads in healthy postmenopausal women. In a control group of 20 women given neither sorbitol nor glucose, the mean +/- SEM fractional radiocalcium absorption rate from a low carrier load was 0.65 +/- 0.05 (fraction of dose/h). In a second group of 10 women the fractional absorption rate from the low carrier load was lower (p less than 0.05) with 10 g sorbitol (0.48 +/- 0.05) than with 10 g glucose (0.65 +/- 0.08). Fractional absorption of radiocalcium from a high carrier load measured in a third group of seven women using two isotopes (oral 45Ca, IV 47Ca) was also lower (p less than 0.001) with 10 g sorbitol (0.22 +/- 0.01, fraction/3 h) than with 10 g glucose (0.29 +/- 0.02). The results suggest that calcium absorption from a low carrier load is unaltered by glucose but that absorption of calcium from both low and high carrier loads is lower with sorbitol than with glucose

  7. Series expansion in fractional calculus and fractional differential equations

    OpenAIRE

    Li, Ming-Fan; Ren, Ji-Rong; Zhu, Tao

    2009-01-01

    Fractional calculus is the calculus of differentiation and integration of non-integer orders. In a recently paper (Annals of Physics 323 (2008) 2756-2778), the Fundamental Theorem of Fractional Calculus is highlighted. Based on this theorem, in this paper we introduce fractional series expansion method to fractional calculus. We define a kind of fractional Taylor series of an infinitely fractionally-differentiable function. Further, based on our definition we generalize hypergeometric functio...

  8. Use of a standard meal to study iron absorption in humans

    International Nuclear Information System (INIS)

    Reddy, M.B.; Cook, J.D.

    1994-01-01

    Iron absorption varies widely between subjects and groups of subjects because of differences in iron status which markedly influence iron assimilation from the gastrointestinal tract. A small dose of isotopically labelled inorganic iron termed the reference dose (3 mg iron as FeSO 4 ) has been used extensively during the past two decades to standardize food iron absorption in human subjects and thereby eliminate the effect of differences in iron status. Recent studies from this laboratory have shown that because of the high variability of absorption from the reference dose, nonheme iron absorption from a standardized meal provides a more reliable means of standardizing absorption from regional diets. We therefore performed initial studies with a rice based meal but we found a relatively high variation in absorption from 2.0 to 4.7% that presumably reflects differences in the phytate content of rice fours. We then undertook the evaluation of meals prepared with farina, a wheat product that is available in most regions of the world. In six different studies from a farina based meal, iron absorption ranged from 3.4 to 6.5%. Nonheme iron absorption from the farina meal when evaluated in separate laboratories extensively engaged in human studies of iron absorption, ranged from 5.1 to 10.8% but when related to the FeSO 4 dose, a more consistent ratio between 0.21 to 0.26 was observed with the exception of one laboratory where a very low absorption of 1.1.% was observed. Percentage absorption from the farina based meal decreased when the iron content of the meal was increased and showed the expected facilitation of absorption when increasing amounts of ascorbic acid were added. By reducing variability and measuring iron absorption from food rather than inorganic iron, we believe that the use of this standard meal will facilitate comparison of iron absorption data obtained in laboratories throughout the world. 4 refs, 2 tabs

  9. A rare cause of recurrent gastrointestinal bleeding: mesenteric hemangioma

    Directory of Open Access Journals (Sweden)

    Zeytunlu Murat

    2009-01-01

    Full Text Available Abstract Lower gastrointestinal hemorrhage accounts for approximately 20% of gastrointestinal hemorrhage. The most common causes of lower gastrointestinal hemorrhage in adults are diverticular disease, inflammatory bowel disease, benign anorectal diseases, intestinal neoplasias, coagulopathies and arterio-venous malformations. Hemangiomas of gastrointestinal tract are rare. Mesenteric hemangiomas are also extremely rare. We present a 25-year-old female who was admitted to the emergency room with recurrent lower gastrointestinal bleeding. An intraluminal bleeding mass inside the small intestinal segment was detected during explorative laparotomy as the cause of the recurrent lower gastrointestinal bleeding. After partial resection of small bowel segment, the histopathologic examination revealed a cavernous hemagioma of mesenteric origin. Although rare, gastrointestinal hemangioma should be thought in differential diagnosis as a cause of recurrent lower gastrointestinal bleeding.

  10. Gastro-Intestinal Parasites of Warthogs (Phacochoerus Africanus ...

    African Journals Online (AJOL)

    Gastro-Intestinal Parasites of Warthogs (Phacochoerus Africanus) from the Nazinga Game Ranch of Burkina Faso. ... the prevalence of gastrointestinal parasites in warthogs from the Nazinga Game Ranch of ... AJOL African Journals Online.

  11. Antioxidant and Anti-Inflammatory Activities of Hydrolysates and Peptide Fractions Obtained by Enzymatic Hydrolysis of Selected Heat-Treated Edible Insects.

    Science.gov (United States)

    Zielińska, Ewelina; Baraniak, Barbara; Karaś, Monika

    2017-09-02

    This study investigated the effect of heat treatment of edible insects on antioxidant and anti-inflammatory activities of peptides obtained by in vitro gastrointestinal digestion and absorption process thereof. The antioxidant potential of edible insect hydrolysates was determined as free radical-scavenging activity, ion chelating activity, and reducing power, whereas the anti-inflammatory activity was expressed as lipoxygenase and cyclooxygenase-2 inhibitory activity. The highest antiradical activity against DPPH • (2,2-diphenyl-1-picrylhydrazyl radical) was noted for a peptide fraction from baked cricket Gryllodes sigillatus hydrolysate (IC 50 value 10.9 µg/mL) and that against ABTS •+ (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical) was the highest for raw mealworm Tenebrio molitor hydrolysate (inhibitory concentration (IC 50 value) 5.3 µg/mL). The peptides obtained from boiled locust Schistocerca gregaria hydrolysate showed the highest Fe 2+ chelation ability (IC 50 value 2.57 µg/mL); furthermore, the highest reducing power was observed for raw G. sigillatus hydrolysate (0.771). The peptide fraction from a protein preparation from the locust S. gregaria exhibited the most significant lipoxygenase and cyclooxygenase-2 inhibitory activity (IC 50 value 3.13 µg/mL and 5.05 µg/mL, respectively).

  12. Gastrointestinal estromal tumor: Presentation of a case

    International Nuclear Information System (INIS)

    Gil Gonzalez, Alexis; Hernandez Perez, Arnaldo; Gonzalez Rodriguez, Diana; Hernandez Fernandez, Diana M; Castanneda Munnoz, Angela

    2009-01-01

    Since the first descriptions made by Golden and Stout, this group of mesenchymal lesions is considered of muscular origin and they were named as leiomyoma, cellular leiomyoma, epithelioid leiomyoma, leiomyoblastoma, bizarre leiomyoma and leiomyosarcoma. But Mazur and Clark created the term estromal tumor only after they began to use the inmunohistochemistry and subsequently showed the absence of muscular markers, and the occasional presence of neural markers. Nowadays, gastrointestinal estromal tumors are called the primary mesenchymal CD117 positive, fusiform or epithelioid tumors of the gastrointestinal tract, epiplon, mesenterio, and retroperitoneum. The gastrointestinal estromal tumors appear at the wall of the digestive tube: stomach (50-60 %), small intestine (20-30 %), large intestine (10 %) and esophagus (5 %), and occasionally in epiplon, mesenterio, and retroperineum (5 %). In our work we present a 67 year-old patient, entered in our hospital for presenting high digestive bleeding. We studied the case, and found a 6 cm tumor of the gastric fundus. The tumor was operated and the definitive results of the pathologic anatomy showed a gastrointestinal estromal tumor

  13. Emergency readmission following acute upper gastrointestinal bleeding

    DEFF Research Database (Denmark)

    Strömdahl, Martin; Helgeson, Johan; Kalaitzakis, Evangelos

    2017-01-01

    OBJECTIVE: To assess the occurrence, clinical predictors, and associated mortality of all-cause emergency readmissions after acute upper gastrointestinal bleeding (AUGIB). PATIENTS AND METHODS: All patients with AUGIB from an area of 600 000 inhabitants in Sweden admitted in a single institution...

  14. Therapy for obesity based on gastrointestinal hormones

    DEFF Research Database (Denmark)

    Bagger, Jonatan I; Christensen, Mikkel; Knop, Filip K

    2011-01-01

    It has long been known that peptide hormones from the gastrointestinal tract have significant impact on the regulation of nutrient metabolism. Among these hormones, incretins have been found to increase insulin secretion, and thus incretin-based therapies have emerged as new modalities...

  15. Upper gastrointestinal endoscopic findings and prevalence of ...

    African Journals Online (AJOL)

    Upper gastrointestinal endoscopic findings and prevalence of Helicobacter pylori infection among adult patients with dyspepsia in northern Tanzania. ... Endoscopy (EGD) for initial work up. Study on antimicrobial susceptibility pattern of H. pylori is recommended to guide choices for evidence based treatment option.

  16. Nutrition in the prevention of gastrointestinal cancer

    NARCIS (Netherlands)

    Brandt, P.A. van den; Goldbohm, R.A.

    2006-01-01

    Diet has been hypothesized to play a role in the etiology of gastrointestinal cancer for a long time. Initially, strong evidence of such effects was found in retrospective epidemiological studies. Dietary habits, in particular those from the distant past, are difficult to measure, however. Results

  17. Sleep, immunity and inflammation in gastrointestinal disorders.

    Science.gov (United States)

    Ali, Tauseef; Choe, James; Awab, Ahmed; Wagener, Theodore L; Orr, William C

    2013-12-28

    Sleep disorders have become a global issue, and discovering their causes and consequences are the focus of many research endeavors. An estimated 70 million Americans suffer from some form of sleep disorder. Certain sleep disorders have been shown to cause neurocognitive impairment such as decreased cognitive ability, slower response times and performance detriments. Recent research suggests that individuals with sleep abnormalities are also at greater risk of serious adverse health, economic consequences, and most importantly increased all-cause mortality. Several research studies support the associations among sleep, immune function and inflammation. Here, we review the current research linking sleep, immune function, and gastrointestinal diseases and discuss the interdependent relationship between sleep and these gastrointestinal disorders. Different physiologic processes including immune system and inflammatory cytokines help regulate the sleep. The inflammatory cytokines such as tumor necrosis factor, interleukin-1 (IL-1), and IL-6 have been shown to be a significant contributor of sleep disturbances. On the other hand, sleep disturbances such as sleep deprivation have been shown to up regulate these inflammatory cytokines. Alterations in these cytokine levels have been demonstrated in certain gastrointestinal diseases such as inflammatory bowel disease, gastro-esophageal reflux, liver disorders and colorectal cancer. In turn, abnormal sleep brought on by these diseases is shown to contribute to the severity of these same gastrointestinal diseases. Knowledge of these relationships will allow gastroenterologists a great opportunity to enhance the care of their patients.

  18. [Biomorphology of gastrointestinal nematodes of small ruminants].

    Science.gov (United States)

    Giannetto, S

    2006-09-01

    Under the term gastrointestinal nematodes are included numerous parasites species of livestock belonging to the families Strongyloididae (Strongyloides), Strongylidae (Chabertia, Oesophagostomum) Trichostrongylidae (Trichostrongylus, Ostertagia, Teladorsagia, Cooperia, Marshallagia), Molineidae (Nematodirus), Ancylostomatidae (Bunostomum) and Trichuridae (Trichuris). This paper reviews the biomorphology aspects of these parasites as well as the controversy by the taxonomists in the classifications.

  19. Pattern of gastrointestinal opportunistic infections among HIV ...

    African Journals Online (AJOL)

    Twenty-two per cent (22%) of these had mixed parasitosis of cryptosporidium and hookworm. There was no significant association of CD4 cells count with intestinal parasitosis. x2 = 5.286 and p=0.259. However marital status was significantly associated with gastrointestinal opportunistic parasitosis with x2 of 12.693, ...

  20. [Fungal infections of the gastrointestinal tract].

    Science.gov (United States)

    Maragkoudakis, Emmanouil; Realdi, Giuseppe; Dore, Maria Pina

    2005-06-01

    In immunocompetent subjects fungal infections of the gastrointestinal tract are uncommon. Candida esophagitis remains the single most common fungal infection in immunocompromised hosts or in H. pylori- infected patients who receive antibiotic therapy. Enteric fungal infections are uncommon even in HIV-infected patients. Antifungal agents such as amphotericin B, ketoconazole, fluconazole, and the various formulations of itraconazole are effective for most cases.

  1. Gastrointestinal and Hepatic Disease in Sjogren Syndrome.

    Science.gov (United States)

    Popov, Yevgeniy; Salomon-Escoto, Karen

    2018-02-01

    Sjogren syndrome (SS) is a lymphocyte-mediated, infiltrative autoimmune disorder characterized by destruction of exocrine glands leading to secretory dysfunction. The typical manifestations include xerostomia and xerophthalmia; however, extensive gastrointestinal involvement is increasingly being recognized, emphasizing the variable and systemic nature of SS. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Primary (AL) amyloidosis with gastrointestinal involvement

    DEFF Research Database (Denmark)

    Madsen, Lone Galmstrup; Gimsing, Peter; Schiødt, Frank V

    2009-01-01

    OBJECTIVE: Immunoglobulin light-chain (AL) amyloidosis is a rare disease that can affect several organs. The aim of this study was to characterize patients with gastrointestinal manifestations of AL amyloidosis, in terms of symptoms, biochemistry, and outcome. MATERIAL AND METHODS: Retrospectivel...

  3. Association between Khat Chewing and Gastrointestinal Disorders ...

    African Journals Online (AJOL)

    The prevalence of gastritis was 580 (57.7%); constipation 235 (23.4%); hemorrhoids 54 (5.4%) and that of dental problems (carries, decay, filling and extraction) was 225 (22.4%) of all study participants. Gastrointestinal disorders were found to be higher among khat chewers, where 64(36.2%) of them had dental problems; ...

  4. Gastrointestinal Injuries Following Blunt Abdominal Trauma In ...

    African Journals Online (AJOL)

    Treatment included segmental resection with end to end anastomosis, wedge resection with anastomosis, exteriorizations stomas, simple excision of the perforation and closure in two layers (gastric perforation). The total mortality was four (21.1%), two of them due to associated injuries. Conclusion: Gastrointestinal injuries ...

  5. Sensory testing of the human gastrointestinal tract.

    NARCIS (Netherlands)

    Brock, C.; Arendt-Nielsen, L.; Wilder-Smith, O.H.G.; Drewes, A.M.

    2009-01-01

    The objective of this appraisal is to shed light on the various approaches to screen sensory information in the human gut. Understanding and characterization of sensory symptoms in gastrointestinal disorders is poor. Experimental methods allowing the investigator to control stimulus intensity and

  6. Gastrointestinal immune responses in HIV infected subjects

    Directory of Open Access Journals (Sweden)

    LRR Castello-Branco

    1996-06-01

    Full Text Available The gut associated lymphoid tissue is responsible for specific responses to intestinal antigens. During HIV infection, mucosal immune deficiency may account for the gastrointestinal infections. In this review we describe the humoral and cellular mucosal immune responses in normal and HIV-infected subjects.

  7. Gastrointestinal diseases in HIV/AIDS

    African Journals Online (AJOL)

    an estimated 65 million people believed to be infected and an estimated. 14 000 new infections ... HIV is a staggering 10 - 20% of the population.1 Gastrointestinal (GI) diseases ... Oral fluconazole is a very successful treatment for ... candidiasis should be started on voriconazole.7 .... habits point to further investigation. An.

  8. Do statins protect against upper gastrointestinal bleeding?

    DEFF Research Database (Denmark)

    Gulmez, Sinem Ezgi; Lassen, Annmarie Touborg; Aalykke, Claus

    2009-01-01

    AIMS: Recently, an apparent protective effect of statins against upper gastrointestinal bleeding (UGB) was postulated in a post hoc analysis of a randomized trial. We aimed to evaluate the effect of statin use on acute nonvariceal UGB alone or in combinations with low-dose aspirin and other...

  9. Angiography and angiotherapy of gastrointestinal tract bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, R.; Grassot, A.; Souchon, R.

    1982-03-01

    In selected patients with upper and lower gastrointestinal hemorrhage there is an indication for angiography. Vasoconstrictive drugs or embolization materials can be submitted through the catheter to stop the hemorrhage (angiotherapy). 81 patients were diagnosed by this method. Treatment through the angiographic catheter followed the diagnostic procedure in 41 cases. The hemorrhage was controlled in 36 patients.

  10. Gastrointestinal bleeding following NSAID ingestion in children

    African Journals Online (AJOL)

    Both presented with a history of fever and passage of bloody stools. There was a positive history of NSAID ingestion in both patients that was prescribed in the referring hospitals. ..... Bostwick HE, Halata MS, Feerick J, Newman LJ, Medow MS. Gastrointestinal bleeding in children following ingestion of low-dose. Ibuprofen.

  11. The Health Problems, Gastrointestinal and Blood Parasites ...

    African Journals Online (AJOL)

    The report on the disease conditions in donkeys in most West African countries is scanty in literature. This study was conducted to identify the health related problems including gastrointestinal and blood parasites of donkeys at the Bolgatanga livestock market in the Upper East region of Ghana from July to December, 2012.

  12. Gastrointestinal tract sonography in fetuses and children

    Energy Technology Data Exchange (ETDEWEB)

    Couture, Alain; Baud, Catherine; Ferran, Jean Louis; Saguintaah, Magali; Veyrac, Corinne [Hopital Arnaud de Villeneuve, 34 - Montpellier (France). Service de Radiologie Pediatrique

    2008-07-01

    Sonography of the gastrointestinal tract in fetuses, neonates and children entails no known biological risk, permits serial scanning and can provide information unobtainable with any other imaging modality. In experienced hands it can be used as the initial imaging technique in a number of gastrointestinal diseases and conditions. This book provides a comprehensive account of the current state of the art regarding sonography in this context. An introductory chapter compares the merits of sonography and magnetic resonance imaging of the fetal gastrointestinal tract. Subsequent chapters focus on the technique, pitfalls and findings in a wide variety of applications, including antropyloric diseases, bowel obstruction, bowel wall thickening, colitis, appendicitis, some types of intussusception, abdominal wall and umbilical abnormalities, intraperitoneal tumors, and trauma. In each case the sonographic morphology is considered in depth with the aid of high-quality illustrations. A concluding chapter comprises a quiz based on 15 case reports. Gastrointestinal Tract Sonography in Fetuses and Children will be of value to all with an interest in this field. (orig.)

  13. Gastrointestinal stromal tumour presenting as gastroduodenal intussusception.

    LENUS (Irish Health Repository)

    Wilson, Mark H

    2012-08-01

    Gastroduodenal intussusception secondary to gastrointestinal stromal tumour is a very rare cause for intestinal obstruction. The diagnosis of this condition can be challenging, as symptoms are often non-specific and intermittent. This article reports a case where the diagnosis was made preoperatively with abdominal imaging and was treated by a combination of endoscopic reduction and laparoscopic resection.

  14. Gastrointestinal cancer after treatment of Hodgkin's disease

    International Nuclear Information System (INIS)

    Birdwell, Sandra H.; Hancock, Steven L.; Varghese, Anna; Cox, Richard S.; Hoppe, Richard T.

    1997-01-01

    Purpose: This study aimed to quantify the risk of gastrointestinal cancer following Hodgkin's disease treatment according to age at treatment, type of treatment, and anatomic sites. Methods and Materials: Cases were identified from the records of 2,441 patients treated for Hodgkin's disease between 1961 and 1994. Follow-up averaged 10.9 years, representing 26,590 person-years of observation. Relative risks (RR) for gastrointestinal cancer incidence and mortality were computed by comparison with expected annualized rates for a general population matched for age, sex, and race. Results: Gastrointestinal cancers developed in 25 patients. The incidence RR was 2.5 [95% confidence interval (CI), 1.5-3.5] and mortality RR was 3.8 (CI, 2.4-4.7). Sites associated with significantly increased risks included the stomach [RR 7.3 (CI, 3.4-13.8)], small intestine [RR 11.6 (CI, 1.9-38.3)], and pancreas [RR 3.5 (CI, 1.1-8.5)]. Risk was significantly elevated after combined modality therapy, RR 3.9 (CI, 2.2-5.6). The risk after radiotherapy alone was 2.0 (CI, 1.0-3.4), not a statistically significant elevation. The RR for gastrointestinal cancer was greatest after treatment at young age and decreased with advancing age. It was significantly elevated within 10 years after treatment [RR 2.0 (CI, 1.1-3.5)] and increased further after 20 years [RR 6.1 (CI, 2.5-12.7)]. Risk assessed by attained age paralleled risk according to age at treatment. Fifteen cases of gastrointestinal cancers arose within the irradiation fields. Conclusion: Patients treated for Hodgkin's disease are at modestly increased risk for secondary gastrointestinal cancer, especially after combined modality therapy and treatment at a young age. Risk was highest more than 20 years after treatment, but was significantly elevated within 10 years. Gastrointestinal sites with increased risk included the stomach, pancreas, and small intestine

  15. Gastrointestinal symptoms in children with acute neuroinfections

    Directory of Open Access Journals (Sweden)

    A.I. Markov

    2018-02-01

    Full Text Available Background. In cases of severe forms of infectious di­seases, in addition to local inflammation, secondary lesions of the gastrointestinal organs may occur. We aimed to study the semiotics and epidemiology of gastrointestinal symptoms in children with acute neuroinfection. Materials and methods. This observational, retrospective, case-control study. We analyzed cases of in-patient treatment of children aged 1 month to 18 years with acute neuroinfections (meningitis, encephalitis and encephalomyelopolyneuropathy. Results. The study included 117 patients with acute central nervous system infections. Clinical symptoms of gastrointestinal infection were observed in 83 (70.9 % children. Among revealed symptoms, disorders of intestinal moti­lity, such as constipation and diarrhea, were prevalent. Manifestations of hepatobiliary system dysfunction included increased transaminase level (alanine aminotransferase (ALT, alkaline phosphatase, gamma-glutamyltransferase (GGTF and/or ultrasound changes (enlargement, diffuse structural changes and were observed in 39.1 % of patients. Among the laboratory parameters, elevated ALT level was observed in 8.3 % of patients, bilirubin was elevated in only one child, alkaline phosphatase was above the age norm in 11.8 %, an increased GGTF above the age norm was observed in 31.3 % of patients. The level of intestinal fatty acid binding protein (I-FABP was elevated in 86.4 %, and L-type fatty acid binding protein (L-FABP — in all (100 % children. Clinical manifestations of gastrointestinal dysfunction (the presence of at least one of the gastrointestinal symptoms had an inverse relationship with the child’s age (rpb = –0.19, p = 0.033, correlated with staying in intensive care unit (odds ratio (OR = +5.25; 95% confidence interval (CI 1.62–16.97, artificial ventilation (OR = +4.5; 95% CI 1.00–21.69 and level of I-FABP (rpb = 0.34, p = 0.019. Conclusions. Among gastrointestinal symptoms in children with

  16. Antibody transferred from the blood to the gastrointestinal tract and its role in enteric immunity of neonatal calves

    International Nuclear Information System (INIS)

    Besser, T.E.

    1986-01-01

    High passive blood immunoglobulin concentrations are associated with decreased infectious enteric disease mortality in neonatal calves. Passive immunoglobulin transferred from the blood to the gastrointestinal tract may explain this protection. To measure the rate at which immunoglobulin G 1 (IgG 1 ) is transferred to the gastrointestinal tract, 125 I-labelled bovine IgG 1 anti-DNP antibody was administered to calves by intravenous injection. The clearance rate of 125 I-IgG 1 from the blood was measured and compared to the rate of 125 I-IgG 1 appearance in the gastrointestinal tract, as measured (1) by the rate of fecal 125 I-IgG 1 excretion, and (2) by the amount of 125 I-IgG 1 in the gastrointestinal tract of calves at necropsy. Rotavirus antibody titers in the gastrointestinal contents of 5- and 10-days-old calves correlated with the calves' serum passive rotavirus antibody titers, and were increased in proportion to the amount of colostral antibody fed on the first day of life. In contrast, when colostral rotavirus antibody was fed to 48-hour-old calves, when absorption of passive immunoglobulin does not occur, there was no measurable increase in antibody in the intestine 5 days later. Intestinal antibody in the 5- and 10-day-old calves therefore resulted from blood antibody transferred to the gastrointestinal tract. Rotavirus antibody administered to calves by parenteral injection protected them from infection and diarrhea after rotavirus challenge. These results indicate that passive blood IgG enters the calf gastrointestinal tract, where it contributes to intestinal immunity

  17. Antibody transferred from the blood to the gastrointestinal tract and its role in enteric immunity of neonatal calves

    Energy Technology Data Exchange (ETDEWEB)

    Besser, T.E.

    1986-01-01

    High passive blood immunoglobulin concentrations are associated with decreased infectious enteric disease mortality in neonatal calves. Passive immunoglobulin transferred from the blood to the gastrointestinal tract may explain this protection. To measure the rate at which immunoglobulin G/sub 1/ (IgG/sub 1/) is transferred to the gastrointestinal tract, /sup 125/I-labelled bovine IgG/sub 1/ anti-DNP antibody was administered to calves by intravenous injection. The clearance rate of /sup 125/I-IgG/sub 1/ from the blood was measured and compared to the rate of /sup 125/I-IgG/sub 1/ appearance in the gastrointestinal tract, as measured (1) by the rate of fecal /sup 125/I-IgG/sub 1/ excretion, and (2) by the amount of /sup 125/I-IgG/sub 1/ in the gastrointestinal tract of calves at necropsy. Rotavirus antibody titers in the gastrointestinal contents of 5- and 10-days-old calves correlated with the calves' serum passive rotavirus antibody titers, and were increased in proportion to the amount of colostral antibody fed on the first day of life. In contrast, when colostral rotavirus antibody was fed to 48-hour-old calves, when absorption of passive immunoglobulin does not occur, there was no measurable increase in antibody in the intestine 5 days later. Intestinal antibody in the 5- and 10-day-old calves therefore resulted from blood antibody transferred to the gastrointestinal tract. Rotavirus antibody administered to calves by parenteral injection protected them from infection and diarrhea after rotavirus challenge. These results indicate that passive blood IgG enters the calf gastrointestinal tract, where it contributes to intestinal immunity.

  18. Gastrointestinal absorption and retention of plutonium-238 in neonatal rats and swine

    International Nuclear Information System (INIS)

    Sullivan, M.F.

    1978-01-01

    Neonatal rats gavaged with 237 Pu or 238 Pu retained a substantial quantity in gut mucosa for a week but absorbed only 2.9% of the 237 Pu. After 140 days the amount retained fell to half that initially deposited. Newborn swine also retained large amounts in the gut and absorbed about 40% of the dose

  19. In silico and in vitro prediction of gastrointestinal absorption from potential drug eremantholide C.

    Science.gov (United States)

    Caldeira, Tamires G; Saúde-Guimarães, Dênia A; Dezani, André B; Serra, Cristina Helena Dos Reis; de Souza, Jacqueline

    2017-11-01

    Analysis of the biopharmaceutical properties of eremantholide C, sesquiterpene lactone with proven pharmacological activity and low toxicity, is required to evaluate its potential to become a drug. Preliminary analysis of the physicochemical characteristics of eremantholide C was performed in silico. Equilibrium solubility was evaluated using the shake-flask method, at 37.0 °C, 100 rpm during 72 h in biorelevant media. The permeability was analysed using parallel artificial membrane permeability assay, at 37.0 °C, 50 rpm for 5 h. The donor compartment was composed of an eremantholide C solution in intestinal fluid simulated without enzymes, while the acceptor compartment consisted of phosphate buffer. Physicochemical characteristics predicted in silico indicated that eremantholide C has a low solubility and high permeability. In-vitro data of eremantholide C showed low solubility, with values for the dose/solubility ratio (ml): 9448.82, 10 389.61 e 15 000.00 for buffers acetate (pH 4.5), intestinal fluid simulated without enzymes (pH 6.8) and phosphate (pH 7.4), respectively. Also, it showed high permeability, with effective permeability of 30.4 × 10 -6 cm/s, a higher result compared with propranolol hydrochloride (9.23 × 10 -6 cm/s). The high permeability combined with its solubility, pharmacological activity and low toxicity demonstrate the importance of eremantholide C as a potential drug candidate. © 2017 Royal Pharmaceutical Society.

  20. Computed tomography in gastrointestinal stromal tumors

    International Nuclear Information System (INIS)

    Ghanem, Nadir; Altehoefer, Carsten; Winterer, Jan; Schaefer, Oliver; Springer, Oliver; Kotter, Elmar; Langer, Mathias; Furtwaengler, Alex

    2003-01-01

    The aim of this study was to define the imaging characteristics of primary and recurrent gastrointestinal stromal tumors (GIST) in computed tomography with respect to the tumor size. Computed tomography was performed in 35 patients with histologically confirmed gastrointestinal stromal tumors and analyzed retrospectively by two experienced and independent radiologist. The following morphologic tumor characteristics of primary (n=20) and (n=16) recurrent tumors were evaluated according to tumor size, shape, homogeneity, density compared with liver, contrast enhancement, presence of calcifications, ulcerations, fistula or distant metastases and the anatomical relationship to the intestinal wall, and the infiltration of adjacent visceral organs. Small GIST ( 5-10 cm) demonstrated an irregular shape, inhomogeneous density on unenhanced and contrast-enhanced images, a combined intra- and extraluminal tumor growth with aggressive findings, and infiltration of adjacent organs in 9 primary diagnosed and 2 recurrent tumors. Large GIST (>10 cm), which were observed in 8 primary tumors and 11 recurrent tumors, showed an irregular margin with inhomogeneous density and aggressive findings, and were characterized by signs of malignancy such as distant and peritoneal metastases. Small recurrent tumors had a similar appearance as compared with large primary tumors. Computed tomography gives additional information with respect to the relationship of gastrointestinal stromal tumor to the gastrointestinal wall and surrounding organs, and it detects distant metastasis. Primary and recurrent GIST demonstrate characteristic CT imaging features which are related to tumor size. Aggressive findings and signs of malignancy are found in larger tumors and in recurrent disease. Computed tomography is useful in detection and characterization of primary and recurrent tumors with regard to tumor growth pattern, tumor size, and varied appearances of gastrointestinal stromal tumors, and indirectly

  1. [Antithrombotic therapy and nonvariceal upper gastrointestinal bleeding].

    Science.gov (United States)

    Belanová, Veronika; Gřiva, Martin

    2015-12-01

    The incidence of acute upper gastrointestinal bleeding is about 85-108/100,000 inhabitants per year, nonvariceal bleeding accounts for 80-90%. Antiplatelet and anticoagulation treatment are the significant risk factors for upper gastrointestinal bleeding. To evaluate the occurrence of upper gastrointestinal bleeding in the general community of patients in a county hospital. And to compare the role played by antiplatelet and anticoagulation drugs and other risk medication. Retrospective analysis of patients over 18 years of age who underwent endoscopy for acute upper gastrointestinal bleeding or anaemia (haemoglobinupper gastrointestinal tract during a hospital stay in 2013 (from January to June). We included 111 patients of average age 69±15 years, men 60%. Nonvariceal bleeding accounted for 90% of the cases. None of the patients with variceal bleeding (10% of patients) took antiplatelet or anticoagulation therapy. There were 100 patients with nonvariceal bleeding of average age 70±15, 61% men. With the symptoms of acute bleeding (hematemesis, melena) presented in 73% of patients. The most frequent cause of bleeding was gastric and duodenal ulcer (54%). 32% of patients with nonvariceal bleeding had antiplatelets, 19% anticoagulants and 10% used nonsteroidal anti-inflammatory drugs, selective serotonin reuptake inhibitors or corticosteroids. 30-days mortality of patients with nonvariceal bleeding was 11%, annual mortality was 23%. There was no significant difference in mortality, blood transfusion requirements or surgical intervention between the patients with antithrombotic agents and without them. 25% of patients (8 patients) using acetylsalicylic acid did not fulfil the indication for this treatment. Among the patients examined by endoscopy for symptomatic nonvariceal bleeding and/or anaemia (haemoglobingastrointestinal bleeding. With regard to that, it is alarming, that there still exists a nonnegligible percentage of patients taking acetylsalicylic acid even

  2. Risk Management for Gastrointestinal Endoscopy in Elderly Patients: Questionnaire for Patients Undergoing Gastrointestinal Endoscopy

    OpenAIRE

    Umegaki, Eiji; Abe, Shinya; Tokioka, Satoshi; Takeuchi, Nozomi; Takeuchi, Toshihisa; Yoda, Yukiko; Murano, Mitsuyuki; Higuchi, Kazuhide

    2009-01-01

    More elderly patients now undergo gastrointestinal endoscopy following recent advances in endoscopic techniques. In this study, we conducted a high-risk survey of endoscopies in Japan, using a questionnaire administered prior to upper gastrointestinal tract endoscopy (UGITE), and identified anticholinergic agents and glucagon preparations as high-risk premedication. We also evaluated the cardiovascular effects of anticholinergic agents and glucagon through measurements of plasma levels of hum...

  3. Absorption of femtosecond laser pulses by atomic clusters

    International Nuclear Information System (INIS)

    Lin Jingquan; Zhang Jie; Li Yingjun; Chen Liming; Lu Tiezheng; Teng Hao

    2001-01-01

    Energy absorption by Xe, Ar, He atomic clusters are investigated using laser pulses with 5 mJ energy in 150 fs duration. Experimental results show that the size of cluster and laser absorption efficiency are strongly dependent on several factors, such as the working pressure of pulse valve, atomic number Z of the gas. Absorption fraction of Xe clusters is as high as 45% at a laser intensity of 1 x 10 15 W/cm 2 with 20 x 10 5 Pa gas jet backing pressure. Absorption of the atomic clusters is greatly reduced by introducing pre-pulses. Ion energy measurements confirm that the efficient energy deposition results in a plasma with very high ion temperature

  4. The prevalence of gastrointestinal nematode infection and their ...

    African Journals Online (AJOL)

    GIN infection was associated with 1.4 litres per cow per day less milk and this ... Gastrointestinal nematode (GIN) infections in cattle are of considerable economic importance .... Table 2. Mean faecal egg counts of gastrointestinal nematodes and the 95% confidence ... 3.2 Gastrointestinal nematode species. The pooled ...

  5. Psychophysiological Associations with Gastrointestinal Symptomatology in Autism Spectrum Disorder

    OpenAIRE

    Ferguson, Bradley J.; Marler, Sarah; Altstein, Lily L.; Lee, Evon Batey; Akers, Jill; Sohl, Kristin; McLaughlin, Aaron; Hartnett, Kaitlyn; Kille, Briana; Mazurek, Micah; Macklin, Eric A.; McDonnell, Erin; Barstow, Mariah; Bauman, Margaret L.; Margolis, Kara Gross

    2016-01-01

    Autism spectrum disorder (ASD) is often accompanied by gastrointestinal disturbances, which also may impact behavior. Alterations in autonomic nervous system functioning are also frequently observed in ASD. The relationship between these findings in ASD is not known. We examined the relationship between gastrointestinal symptomatology, examining upper and lower gastrointestinal tract symptomatology separately, and autonomic nervous system functioning, as assessed by heart rate variability and...

  6. Gastrointestinal motility during cardiopulmonary bypass : A sonomicrometric study

    NARCIS (Netherlands)

    Gu, YJ; de Kroon, TL; Elstrodt, JM; Rakhorst, G

    Cardiopulmonary bypass (CPB) is known to impair the integrity of the gastrointestinal tract. However, little is known about the movement behavior of the gastrointestinal tract during CPB. This study was aimed to assess the gastrointestinal motility with sonomicrometry, a distance measurement using

  7. Gastrointestinal Fistula: Audit of management in a remote hospital ...

    African Journals Online (AJOL)

    Background: The management of gastrointestinal fistula continues to present considerable challenge to the surgeon in general and gastrointestinal surgeon in particular. Objectives: To audit the management and report the outcome of the gastrointestinal fistula in a remote hospital. Setup: Eldamazeen Hospital is a regional ...

  8. FRACTIONS: CONCEPTUAL AND DIDACTIC ASPECTS

    OpenAIRE

    Sead Rešić; Ismet Botonjić; Maid Omerović

    2016-01-01

    Fractions represent the manner of writing parts of whole numbers (integers). Rules for operations with fractions differ from rules for operations with integers. Students face difficulties in understanding fractions, especially operations with fractions. These difficulties are well known in didactics of Mathematics throughout the world and there is a lot of research regarding problems in learning about fractions. Methods for facilitating understanding fractions have been discovered...

  9. Fractional-order devices

    CERN Document Server

    Biswas, Karabi; Caponetto, Riccardo; Mendes Lopes, António; Tenreiro Machado, José António

    2017-01-01

    This book focuses on two specific areas related to fractional order systems – the realization of physical devices characterized by non-integer order impedance, usually called fractional-order elements (FOEs); and the characterization of vegetable tissues via electrical impedance spectroscopy (EIS) – and provides readers with new tools for designing new types of integrated circuits. The majority of the book addresses FOEs. The interest in these topics is related to the need to produce “analogue” electronic devices characterized by non-integer order impedance, and to the characterization of natural phenomena, which are systems with memory or aftereffects and for which the fractional-order calculus tool is the ideal choice for analysis. FOEs represent the building blocks for designing and realizing analogue integrated electronic circuits, which the authors believe hold the potential for a wealth of mass-market applications. The freedom to choose either an integer- or non-integer-order analogue integrator...

  10. Optical absorption in dendrimers

    International Nuclear Information System (INIS)

    Supritz, C.; Engelmann, A.; Reineker, P.

    2004-01-01

    Dendrimers are highly branched molecules, which are expected to be useful, for example, as efficient artificial light harvesting systems in nano-technological applications. There are two different classes of dendrimers: compact dendrimers with constant distance between neighboring branching points throughout the macromolecule and extended dendrimers, where this distance increases from the system periphery to the center. We investigate the linear absorption spectra of these dendrimer types using the Frenkel exciton concept. The electron-phonon interaction is taken into account by introducing a heat bath that interacts with the exciton in a stochastic manner

  11. Rapidly variable relatvistic absorption

    Science.gov (United States)

    Parker, M.; Pinto, C.; Fabian, A.; Lohfink, A.; Buisson, D.; Alston, W.; Jiang, J.

    2017-10-01

    I will present results from the 1.5Ms XMM-Newton observing campaign on the most X-ray variable AGN, IRAS 13224-3809. We find a series of nine absorption lines with a velocity of 0.24c from an ultra-fast outflow. For the first time, we are able to see extremely rapid variability of the UFO features, and can link this to the X-ray variability from the inner accretion disk. We find a clear flux dependence of the outflow features, suggesting that the wind is ionized by increasing X-ray emission.

  12. Geospatial Absorption and Regional Effects

    Directory of Open Access Journals (Sweden)

    IOAN MAC

    2009-01-01

    Full Text Available The geospatial absorptions are characterized by a specific complexity both in content and in their phenomenological and spatial manifestation fields. Such processes are differentiated according to their specificity to pre-absorption, absorption or post-absorption. The mechanisms that contribute to absorption are extremely numerous: aggregation, extension, diffusion, substitution, resistivity (resilience, stratification, borrowings, etc. Between these mechanisms frequent relations are established determining an amplification of the process and of its regional effects. The installation of the geographic osmosis phenomenon in a given territory (a place for example leads to a homogenization of the geospatial state and to the installation of the regional homogeneity.

  13. Bioavailability and the mechanisms of intestinal absorption of iron from ferrous ascorbate and ferric polymaltose in experimental animals

    International Nuclear Information System (INIS)

    Johnson, G.; Jacobs, P.

    1990-01-01

    The comparative bioavailability from matching quantities of iron in the form of ferrous ascorbate or ferric polymaltose was defined in rats. Studies were carried out in the intact animals under basal conditions and also when requirements for this metal were either increased or decreased by manipulating stores or erythropoietic activity. No significant difference was found in the total quantity of iron absorbed from either salt or complex under any of these circumstances, suggesting that the mucosal mechanism regulating the overall process was common to both. However, the rate of transfer from the lumen into portal blood was distinctive, reaching a maximum with salt at 30 min compared to 24 h for the complex. To explore the possibility that iron from the two sources was initially handled by different subcellular pathways, the radiolabeled compounds were instilled into loops of bowel that had been isolated between ligatures in vivo. Enterocytes were harvested and fractionated, and incorporation into ferritin and transferrin was determined using RIA. From salt, iron appeared rapidly in duodenal but not ileal ferritin, whereas mucosal transferrin increased under conditions of stimulated absorption, suggesting that this protein may act as a shuttle for the metal. In contrast, iron from polymaltose showed a cumulative incorporation into duodenal ferritin over time that correlated with iron absorption, defined by the appearance of radiolabel in the serum and in the carcass; a similar pattern was demonstrable in ileal mucosal cells. Conversely, binding of iron to transferrin was minimal. No iron polymaltose was found within the mucosal cells. It is suggested that the low rate of iron transfer from this ferric complex may reflect its extracellular breakdown in the lumen of the gastrointestinal tract

  14. Stability of milk fat globule membrane proteins toward human enzymatic gastrointestinal digestion.

    Science.gov (United States)

    Le, T T; Van de Wiele, T; Do, T N H; Debyser, G; Struijs, K; Devreese, B; Dewettinck, K; Van Camp, J

    2012-05-01

    The milk fat globule membrane (MFGM) fraction refers to the thin film of polar lipids and membrane proteins that surrounds fat globules in milk. It is its unique biochemical composition that renders MFGM with some beneficial biological activities, such as anti-adhesive effects toward pathogens. However, a prerequisite for the putative bioactivity of MFGM is its stability during gastrointestinal digestion. We, therefore, subjected MFGM material, isolated from raw milk, to an in vitro enzymatic gastrointestinal digestion. Sodium dodecyl sulfate PAGE, in combination with 2 staining methods, Coomassie Blue and periodic acid Schiff staining, was used to evaluate polypeptide patterns of the digest, whereas mass spectrometry was used to confirm the presence of specific MFGM proteins. Generally, it was observed that glycoproteins showed higher resistance to endogenous proteases compared with non-glycosylated proteins. Mucin 1 displayed the highest resistance to digestion and a considerable part of this protein was still detected at its original molecular weight after gastric and small intestine digestion. Cluster of differentiation 36 was also quite resistant to pepsin. A significant part of periodic acid Schiff 6/7 survived the gastric digestion, provided that the lipid moiety was not removed from the MFGM material. Overall, MFGM glycoproteins are generally more resistant to gastrointestinal digestion than serum milk proteins and the presence of lipids, besides glycosylation, may protect MFGM glycoproteins from gastrointestinal digestion. This gastrointestinal stability makes MFGM glycoproteins amenable to further studies in which their putative health-promoting effects can be explored. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  15. Fractional gradient and its application to the fractional advection equation

    OpenAIRE

    D'Ovidio, M.; Garra, R.

    2013-01-01

    In this paper we provide a definition of fractional gradient operators, related to directional derivatives. We develop a fractional vector calculus, providing a probabilistic interpretation and mathematical tools to treat multidimensional fractional differential equations. A first application is discussed in relation to the d-dimensional fractional advection-dispersion equation. We also study the connection with multidimensional L\\'evy processes.

  16. Pregnant woman mode for absorbed fraction calculations

    International Nuclear Information System (INIS)

    Cloutier, R.J.; Snyder, W.S.; Watson, E.E.

    1977-01-01

    The most radiation-sensitive segment of our population is the developing fetus. Until recently, methods available for calculating the dose to the fetus were inadequate because a model for the pregnant woman was not available. Instead, the Snyder and Fisher model of Reference Man, which includes a uterus, was frequently used to calculate absorbed fractions when the source was in various organs of the body and the nongravid uterus was the target. These values would be representative of the dose to the embryo during the early stages of pregnancy. Unfortunately, Reference Man is considerable larger than Reference Woman. The authors recently reported on the design of a Reference Woman phantom that has dimensions quite similar to the ICRP Reference Woman. This phantom was suitable for calculating the dose to the embryo during early stages of pregnancy (0 to 3 mo.), but was not suitable for the later stages of pregnancy because of the changing shape of the mother and the displacement of several abdominal organs brought about by the growth of the uterus and fetus. The models of Reference Woman that were subsequently developed for each month of pregnancy are described. The models take into account the growth of the uterus and fetus and the repositioning of the various abdominal organs. These models have been used to calculate absorbed fractions for the fetus as a target and the gastrointestinal tract as a source of radiation for twelve photon energies ranging from 10 keV to 4 MeV

  17. Gastrointestinal Injuries in Blunt Abdominal Traumas.

    Science.gov (United States)

    Gönüllü, D; Ilgun, S; Gedik, M L; Demiray, O; Öner, Z; Er, M; Köksoy, F N

    2015-01-01

    To discuss the efficiency of RTS (Revised TraumaScore), ISS (Injury Severity Score), and factors that affect mortality and morbidity in gastrointestinal injuries due to blunt trauma.Method and methods: Patients with gastrointestinal injuries due to blunt trauma operated within the last six years have been studied retrospectively in terms of demographics,injury mechanism and localization, additional injuries, RTS and ISS, operative technique, morbidity, mortality and duration of hospitalization. Of the eighteen cases, cause of injury was a traffic accident for 11 (61.1%), fall from height for 5 (27%) and physical attack for 2 (11%). Among the eighteen patients,there were 21 gastrointestinal injuries (11 intestinal, 6 colon,3 duodenum, 1 stomach). 10 (55.6%) had additional intraabdominal injuries while the number for extra-abdominal injuries were 12 (66.7%). Primary suture (10), segmentary resection (9) and pyloric exclusion (2) were the operations performed for the twenty-one gastrointestinal injuries.Although statistically not significant, 13(72.2%) patients with additional injuries compared with 5 (27.8%) patients with isolated gastrointestinal injuries, were found to have lower RTS (7.087/7.841), higher ISS (19.4/12.2), longer duration of hospitalization (11.5/8.4 day) as well as higher morbidity (7/1) and mortality (2/0) rates. Comparing the RTS (7.059/7.490) of patients who have and have not developed morbidity revealed no significant difference.However, ISS (23.9/12.2) was significantly higher in patients who have developed morbidity (p=0.003). RTS (6.085 7.445) and ISS (39.5/14.6) of patients who have survived were significantly different than patients who have not(p=0.037 and p=0.023, respectively) Additional injuries in patients with gastrointestinal injury due blunt abdominal traumas increases, although not significantly, morbidity, mortality and duration of hospitalization even when operated early. High ISS is significantly related to the risk of both

  18. Sweet Work with Fractions

    Science.gov (United States)

    Vinogradova, Natalya; Blaine, Larry

    2013-01-01

    Almost everyone loves chocolate. However, the same cannot be said about fractions, which are loved by markedly fewer. Middle school students tend to view them with wary respect, but little affection. The authors attempt to sweeten the subject by describing a type of game involving division of chocolate bars. The activity they describe provides a…

  19. Fermion Number Fractionization

    Indian Academy of Sciences (India)

    Srimath

    1 . In tro d u ctio n. T he N obel P rize in C hem istry for the year 2000 w as aw arded to A lan J H ... soliton, the ground state of the ferm ion-soliton system can have ..... probability density,in a heuristic w ay that a fractional ferm ion num ber m ay ...

  20. Momentum fractionation on superstrata

    International Nuclear Information System (INIS)

    Bena, Iosif; Martinec, Emil; Turton, David; Warner, Nicholas P.

    2016-01-01

    Superstrata are bound states in string theory that carry D1, D5, and momentum charges, and whose supergravity descriptions are parameterized by arbitrary functions of (at least) two variables. In the D1-D5 CFT, typical three-charge states reside in high-degree twisted sectors, and their momentum charge is carried by modes that individually have fractional momentum. Understanding this momentum fractionation holographically is crucial for understanding typical black-hole microstates in this system. We use solution-generating techniques to add momentum to a multi-wound supertube and thereby construct the first examples of asymptotically-flat superstrata. The resulting supergravity solutions are horizonless and smooth up to well-understood orbifold singularities. Upon taking the AdS_3 decoupling limit, our solutions are dual to CFT states with momentum fractionation. We give a precise proposal for these dual CFT states. Our construction establishes the very nontrivial fact that large classes of CFT states with momentum fractionation can be realized in the bulk as smooth horizonless supergravity solutions.

  1. Fractional Differential Equation

    Directory of Open Access Journals (Sweden)

    Moustafa El-Shahed

    2007-01-01

    where 2<α<3 is a real number and D0+α is the standard Riemann-Liouville fractional derivative. Our analysis relies on Krasnoselskiis fixed point theorem of cone preserving operators. An example is also given to illustrate the main results.

  2. Vapor liquid fraction determination

    International Nuclear Information System (INIS)

    1980-01-01

    This invention describes a method of measuring liquid and vapor fractions in a non-homogeneous fluid flowing through an elongate conduit, such as may be required with boiling water, non-boiling turbulent flows, fluidized bed experiments, water-gas mixing analysis, and nuclear plant cooling. (UK)

  3. Brewing with fractionated barley

    NARCIS (Netherlands)

    Donkelaar, van L.H.G.

    2016-01-01

    Brewing with fractionated barley

    Beer is a globally consumed beverage, which is produced from malted barley, water, hops and yeast. In recent years, the use of unmalted barley and exogenous enzymes have become more popular because they enable simpler processing and reduced environmental

  4. Fractionation and rectification apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Sauerwald, A

    1932-05-25

    Fractionation and rectifying apparatus with a distillation vessel and a stirring tube, drainage tubes leading from its coils to a central collecting tube, the drainage tubes being somewhat parallel and attached to the outer half of the stirring tube and partly on the inner half of the central collecting tube, whereby distillation and rectification can be effected in a single apparatus.

  5. Fractional charge search

    International Nuclear Information System (INIS)

    Innes, W.; Klein, S.; Perl, M.; Price, J.C.

    1982-06-01

    A device to search for fractional charge in matter is described. The sample is coupled to a low-noise amplifier by a periodically varying capacitor and the resulting signal is synchronously detected. The varying capacitor is constructed as a rapidly spinning wheel. Samples of any material in volumes of up to 0.05 ml may be searched in less than an hour

  6. The application of PET-CT in gastrointestinal stromal tumor

    International Nuclear Information System (INIS)

    Xian Weijun; Feng Yanlin

    2009-01-01

    Gastrointestinal stromal tumor (GIST) is a mesenchymal neoplasm of uncertain malignant potential that arises predominantly in the gastrointestinal tract. Due to lack of specific physical signs, imagin g-x examination is an important auxiliary means in diagnosing gastrointestinal stromal tumor. Compared to other conventional imaging examinations, PET-CT has demonstrated unique superiority in staging, response evaluation and follow-up of gastrointestinal stromal tumor. And now it presents an overview of the application valuation of PET-CT and related imaging technology in gastrointestinal stromal tumor as follow. (authors)

  7. Pro-inflammatory cytokines play a key role in the development of radiotherapy-induced gastrointestinal mucositis

    Directory of Open Access Journals (Sweden)

    Logan Richard M

    2010-03-01

    Full Text Available Abstract Background Mucositis is a toxic side effect of anti-cancer treatments and is a major focus in cancer research. Pro-inflammatory cytokines have previously been implicated in the pathophysiology of chemotherapy-induced gastrointestinal mucositis. However, whether they play a key role in the development of radiotherapy-induced gastrointestinal mucositis is still unknown. Therefore, the aim of the present study was to characterise the expression of pro-inflammatory cytokines in the gastrointestinal tract using a rat model of fractionated radiotherapy-induced toxicity. Methods Thirty six female Dark Agouti rats were randomly assigned into groups and received 2.5 Gys abdominal radiotherapy three times a week over six weeks. Real time PCR was conducted to determine the relative change in mRNA expression of pro-inflammatory cytokines IL-1β, IL-6 and TNF in the jejunum and colon. Protein expression of IL-1β, IL-6 and TNF in the intestinal epithelium was investigated using qualitative immunohistochemistry. Results Radiotherapy-induced sub-acute damage was associated with significantly upregulated IL-1β, IL-6 and TNF mRNA levels in the jejunum and colon. The majority of pro-inflammatory cytokine protein expression in the jejunum and colon exhibited minimal change following fractionated radiotherapy. Conclusions Pro-inflammatory cytokines play a key role in radiotherapy-induced gastrointestinal mucositis in the sub-acute onset setting.

  8. Gastrointestinal Physiology During Head Down Tilt Bedrest in Human Subjects

    Science.gov (United States)

    Vaksman, Z.; Guthienz, J.; Putcha, L.

    2008-01-01

    Introduction: Gastrointestinal (GI) motility plays a key role in the physiology and function of the GI tract. It directly affects absorption of medications and nutrients taken by mouth, in addition to indirectly altering GI physiology by way of changes in the microfloral composition and biochemistry of the GI tract. Astronauts have reported nausea, loss of appetite and constipation during space flight all of which indicate a reduction in GI motility and function similar to the one seen in chronic bed rest patients. The purpose of this study is to determine GI motility and bacterial proliferation during -6 degree head down tilt bed rest (HTD). Methods: Healthy male and female subjects between the ages of 25-40 participated in a 60 day HTD study protocol. GI transit time (GITT) was determined using lactulose breath hydrogen test and bacterial overgrowth was measured using glucose breath hydrogen test. H. Pylori colonization was determined using C13-urea breath test (UBIT#). All three tests were conducted on 9 days before HDT, and repeated on HDT days 2, 28, 58, and again on day 7 after HDT. Results: GITT increased during HTD compared to the respective ambulatory control values; GITT was significantly lower on day 7 after HTD. A concomitant increase in bacterial colonization was also noticed during HDT starting after approximately 28 days of HDT. However, H. Pylori proliferation was not recorded during HDT as indicated by UBIT#. Conclusion: GITT significantly decreased during HDT with a concomitant increase in the proliferation of GI bacterial flora but not H. pylori.

  9. Physiologically Based Pharmacokinetic and Absorption Modeling for Osmotic Pump Products.

    Science.gov (United States)

    Ni, Zhanglin; Talattof, Arjang; Fan, Jianghong; Tsakalozou, Eleftheria; Sharan, Satish; Sun, Dajun; Wen, Hong; Zhao, Liang; Zhang, Xinyuan

    2017-07-01

    Physiologically based pharmacokinetic (PBPK) and absorption modeling approaches were employed for oral extended-release (ER) drug products based on an osmotic drug delivery system (osmotic pumps). The purpose was to systemically evaluate the in vivo relevance of in vitro dissolution for this type of formulation. As expected, in vitro dissolution appeared to be generally predictive of in vivo PK profiles, because of the unique feature of this delivery system that the in vitro and in vivo release of osmotic pump drug products is less susceptible to surrounding environment in the gastrointestinal (GI) tract such as pH, hydrodynamic, and food effects. The present study considered BCS (Biopharmaceutics Classification System) class 1, 2, and 3 drug products with half-lives ranging from 2 to greater than 24 h. In some cases, the colonic absorption models needed to be adjusted to account for absorption in the colon. C max (maximum plasma concentration) and AUCt (area under the concentration curve) of the studied drug products were sensitive to changes in colon permeability and segmental GI transit times in a drug product-dependent manner. While improvement of the methodology is still warranted for more precise prediction (e.g., colonic absorption and dynamic movement in the GI tract), the results from the present study further emphasized the advantage of using PBPK modeling in addressing product-specific questions arising from regulatory review and drug development.

  10. Physiological Importance and Mechanisms of Protein Hydrolysate Absorption

    Science.gov (United States)

    Zhanghi, Brian M.; Matthews, James C.

    Understanding opportunities to maximize the efficient digestion and assimilation by production animals of plant- and animal-derived protein products is critical for farmers, nutritionists, and feed manufacturers to sustain and expand the affordable production of high quality animal products for human consumption. The challenge to nutritionists is to match gastrointestinal tract load to existing or ­inducible digestive and absorptive capacities. The challenge to feed manufacturers is to develop products that are efficient substrates for digestion, absorption, and/or both events. Ultimately, the efficient absorption of digesta proteins depends on the mediated passage (transport) of protein hydrosylate products as dipeptides and unbound amino acids across the lumen- and blood-facing membranes of intestinal absorptive cells. Data testing the relative efficiency of supplying protein as hydrolysates or specific dipeptides versus as free amino acids, and the response of animals in several physiological states to feeding of protein hydrolysates, are presented and reviewed in this chapter. Next, data describing the transport mechanisms responsible for absorbing protein hydrolysate digestion products, and the known and putative regulation of these mechanisms by their substrates (small peptides) and hormones are presented and reviewed. Several conclusions are drawn regarding the efficient use of protein hydrolysate-based diets for particular physiological states, the economically-practical application of which likely will depend on technological advances in the manufacture of protein hydrolysate products.

  11. Radiodiagnosis of tumours of gastrointestinal tract

    International Nuclear Information System (INIS)

    Sokolov, Yu.N.; Antonovich, V.B.

    1981-01-01

    Systematic description of X-ray picture of tumours of gastrointestinal tract organs is given. The possibilities of contemporary methods of X-ray examination in their revealing are shown. Clinical and X-ray trend of tumour diagnosis is underlined. The basic and accessory symptoms are analyzed from which X-ray semiotics of tumours is turned out. The expressiveness of X-ray symptoms is shown in relation to morphological forms and localization of the tumours. Much attention is given to radiodiagnosis of early tumours of stomach. Differential diagnosis of tumours with non-tumoural diseases is given. X-ray semiotics of lesions of gastrointestinal tract organs in malignant diseases of blood system is presented [ru

  12. Nanotechnology in gastrointestinal endoscopy: A primer

    Directory of Open Access Journals (Sweden)

    Ashish Kumar Jha

    2012-01-01

    Full Text Available Nanotechnology is the understanding, control of matter and development of engineered devices in nanometer range (1-100 nm. Nanoparticles have different physicochemical properties (small size, large surface area to volume ratio, and high reactivity in comparison to bulk materials of the same composition. The nanotechnology has proved its usefulness in early diagnosis, proteonomics, imaging diagnostics and multifunctional therapeutics. Recent studies have shown its role in early diagnosis and targeted therapy of various gastrointestinal disorders such as hepatitis B virus and hepatitis C virus related liver disease, inflammatory bowel disease, gastric ulcer, and malignancy. Application of this technology appears promising in diagnostic and therapeutic endoscopy such as the endoscopic hemostasis of peptic ulcer bleeding, prevention of clogging of plastic stent and advance capsule endoscopy. This article will highlight the basic concepts of nanotechnology and its potential application in gastrointestinal endoscopy.

  13. Effects of ageing on gastrointestinal motor function

    DEFF Research Database (Denmark)

    Madsen, Jan Lysgård; Graff, Jesper

    2004-01-01

    BACKGROUND: Existing data on the effect of ageing on gastrointestinal motility are few. In this study, we assessed the propulsive effect of all main segments of the gastrointestinal tract in a group of healthy older people. METHODS: 16 healthy volunteers (eight women, eight men) of mean age 81...... mass index and smoking on the motility variables. The results were compared with data from 16 healthy individuals (eight women, eight men) of mean age 24 years (range 20-30 years). RESULTS: Advanced age did not influence gastric emptying or small intestinal transit rate. Older individuals had a slower.......0022). CONCLUSION: Normal ageing seems to reduce the propulsive capacity of the colon, whereas gastric and small intestinal motility is not affected....

  14. Characteristics of Emergency Gastrointestinal Stromal Tumor (GIST).

    Science.gov (United States)

    Uçar, Ahmet Deniz; Oymaci, Erkan; Carti, Erdem Bariş; Yakan, Savaş; Vardar, Enver; Erkan, Nazif; Mehmet, Yildirim

    2015-05-01

    Gastrointestinal Stromal Tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract (GIT). Importance of GISTs is increasing while surgeons are facing with more frequent either in emergency setting of elective cases. Delineating the presentation and management of emergency GIST is important. From 2005 to 2014, emergency cases with final diagnosis of GIST were examined retrospectively. Total of 13 operated cases were evaluated by patients characteristics, clinical presentation, operational findings and postoperative prognosis. There were 9 male and 4 female with the mean age of 48.15 years. The most frequent presentations are ileus and GIT hemorrhage both covering the 84% of patients. Small bowel was the dominating site with ileus. Stomach was the second frequent site of the disease with the finding of hemorrhage. Emergency patients are more likely to come with small bowel GIST and obstruction symptoms. Hemorrhage is the most frequent symptom for emergency GIST of stomach and duodenum.

  15. Dermatologic symptoms associated with gastrointestinal neoplasia

    Directory of Open Access Journals (Sweden)

    Beata Młynarczyk-Bonikowska

    2017-03-01

    Full Text Available Gastrointestinal tumors are among the most common neoplastic causes of death worldwide. Presence of characteristic skin lesions can allow faster diagnosis and therapy and this way can increase the probability of a cure. In the paper we present the most important paraneoplastic syndromes that can coexist with gastrointestinal malignancy including colon, gastric, esophagus and pancreatic cancers. We take into account genetic syndromes such as Cowden syndrome, familial atypical multiple mole melanoma syndrome (FAMMM (melanoma/pancreatic cancer, Clarke Howel-Evans, Peutz-Jeghers, Muir-Torre, Gardner syndromes and acquired syndromes such as acantosis nigricans maligna, tripe palms, Leser-Trelat, Bazex, hypertrichosis languinosa, erythema gyratum repens , carcinoid and glucagonoma syndrome. We also include cutaneous metastases and coexistence of neoplasia in some cases of dermatomyositis.

  16. Upper gastrointestinal bleeding in irbid, jordan

    International Nuclear Information System (INIS)

    Banisalamah, A.A.; Mraiat, Z.M.

    2007-01-01

    To define the various causes of nonvariceal upper gastrointestinal bleeding, to outline management modalities and to determine the final outcome of patients. A retrospective analysis of patients presenting with upper gastrointestinal (UGI) bleeding from January 2003 to December 2006 (4 years) was conducted. Patients with endoscopically proven variceal bleeding were excluded. Out of the 120 patients, most of the patients belonged to an age group of more than 50 years (mean 48.5 years). Haematemesis was the most common presentation and Acute Gastric Mucosal Lesion (AGML) was the most frequently encountered lesion. The cause of bleeding was not identified in 10 patients (undetermined group). Twenty-two (18.3%) underwent surgery and we had an overall mortality of 15.8%. AGML being the leading cause can be managed conservatively most of the time. There is a male preponderance and the incidence and mortality increases with advancing age. The undetermined group remains a diagnostic problem. (author)

  17. Computed tomography of the gastrointestinal tract

    International Nuclear Information System (INIS)

    Megibow, A.J.; Balthazar, E.J.

    1986-01-01

    New generation CT scans combined with high-detail barium studies have now allowed radiologists to see and gain a more complete understanding of the wall and surrounding structures of the gastrointestinal tract. The editors state that their intent is to ''present in a comprehensive volume an up-to-date evaluation o the role, significance, indications, and limitations of computed tomography of the gastrointestinal tract.'' There is an initial chapter on CT scanning techniques and the use of oral contrast agents. Chapters follow on Ct of the esophagus, stomach, duodenum, small bowel, and colon. The chapters start with a description of the anatomic structures and then cover in detail common pathologic conditions that affect the organ. Indications for examinations are also included in many chapters. There are final chapters on percutaneous drainage of abscesses and fluid collections and on radiologic-patholoic correlation of some of the more common entities

  18. Imaging of gastrointestinal stromal tumour (GIST)

    International Nuclear Information System (INIS)

    Lau, S.; Tam, K.F.; Kam, C.K.; Lui, C.Y.; Siu, C.W.; Lam, H.S.; Mak, K.L.

    2004-01-01

    Gastrointestinal stromal tumour (GIST) represents the most common kind of mesenchymal tumour that arises from the alimentary tract. GIST is currently defined as a gastrointestinal tract mesenchymal tumour containing spindle cells (or less commonly epithelioid cells or rarely both) and showing CD117 (c-kit protein) positivity. Targeted molecular therapy of non-resectable GIST using imatinib, a specific tyrosine kinase receptor inhibitor, represents a real milestone in the management of solid malignancy. Imaging studies, both anatomical and functional, are playing an increasingly important role in management of patients with GIST. This review illustrates the radiological appearance of GISTs and the site-specific roles of each imaging tool. Clinical features and radiological differential diagnosis of GIST are also discussed

  19. In vitro chemopreventive properties of peptides released from quinoa (Chenopodium quinoa Willd.) protein under simulated gastrointestinal digestion.

    Science.gov (United States)

    Vilcacundo, Rubén; Miralles, Beatriz; Carrillo, Wilman; Hernández-Ledesma, Blanca

    2018-03-01

    Because of the continuous and direct interaction between the digestive tract and foods, dietary compounds represent an interesting source of chemopreventive agents for gastrointestinal health. In this study, the influence of a standardized static in vitro gastrointestinal digestion model on the release of peptides with chemopreventive potential from quinoa protein was investigated. Gastroduodenal digests and fractions collected by ultrafiltration were evaluated for their in plate oxygen radical absorbance capacity and in vitro colon cancer cell viability inhibitory activity. Highest effects were observed in the digests obtained during the intestinal phase, with fraction containing peptides 5kDa showing the greatest anti-cancer effects. Seventeen potential bioactive peptides derived from quinoa proteins have been identified. These proteins might be utilized as new ingredients in the development of functional foods or nutraceuticals with the aim of reducing oxidative stress-associated diseases, including cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. [Expression of neuropeptide Y and long leptin receptor in gastrointestinal tract of giant panda].

    Science.gov (United States)

    Luo, Qihui; Tang, Xiuying; Chen, Zhengli; Wang, Kaiyu; Wang, Chengdong; Li, Desheng; Li, Caiwu

    2015-08-01

    To study the expression and distribution of neuropeptide Y (NPY) and long leptin receptor (OB-Rb) in the gastrointestinal tract of giant panda, samples of three animals were collected from the key laboratory for reproduction and conservation genetics of endangered wildlife of Sichuan province, China conservation and research center for the giant panda. Paraffin sections of giant panda gastrointestinal tissue samples were observed using hematoxylin-eosin staining (HE) and strept actividin-biotin complex immunohistochemical staining (IHC). The results show that the intestinal histology of three pandas was normal and no pathological changes, and there were rich single-cell and multi-cell mucous glands, long intestinal villi and thick muscularis mucosa and muscle layer. Positive cells expressing NPY and OB-Rb were widely detected in the gastrointestinal tract by IHC methods. NPY positive nerve fibers and neuronal cell were widely distributed in submucosal plexus and myenteric plexus, especially in the former. They were arranged beaded or point-like shape. NPY positive cells were observed in the shape of ellipse and polygon and mainly located in the mucous layer and intestinal glands. OB-Rb positive cells were mainly distributed in the mucous layer and the laminae propria, especially the latter. These results confirmed that NPY and OB-Rb are widely distributed in the gut of the giant panda, which provide strong reference for the research between growth and development, digestion and absorption, and immune function.

  1. Predictive tools for the evaluation of microbial effects on drugs during gastrointestinal passage.

    Science.gov (United States)

    Pieper, Ines A; Bertau, Martin

    2010-06-01

    Predicting drug metabolism after oral administration is highly complex, yet indispensable. Hitherto, drug metabolism mainly focuses on hepatic processes. In the intestine, drug molecules encounter the metabolic activity of microorganisms prior to absorption through the gut wall. Drug biotransformation through the gastrointestinal microflora has the potential to evoke serious problems because the metabolites formed may cause unexpected and undesired side effects in patients. Hence, in the course of drug development, the question has to be addressed if microbially formed metabolites are physiologically active, pharmaceutically active or even toxic. In order to provide answers to these questions and to keep the number of laboratory tests needed low, predictive tools - in vivo as well as in silico - are invaluable. This review gives an outline of the current state of the art in the field of predicting the drug biotransformation through the gastrointestinal microflora on several levels of modelling. A comprehensive review of the literature with a thorough discussion on assets and drawbacks of the different modelling approaches. The impact of the gastrointestinal drug biotransformation on patients' health will grow with increasing complexity of drug entities. Predicting metabolic fates of drugs by combining in vitro and in silico models provides invaluable information which will be suitable to particularly reduce in vivo studies.

  2. Effects of Kampo on functional gastrointestinal disorders

    OpenAIRE

    Oka, Takakazu; Okumi, Hirokuni; Nishida, Shinji; Ito, Takashi; Morikiyo, Shinichi; Kimura, Yoko; Murakami, Masato

    2014-01-01

    This article reviews the effectiveness of Kampo (traditional Japanese herbal medicine) in the treatment of functional gastrointestinal disorders, especially functional dyspepsia (FD) and irritable bowel syndrome (IBS). The results of four randomized, controlled trials (RCTs) suggested the usefulness of rikkunshito in relieving the subjective symptoms of patients with FD. Rikkunshito significantly improved not only gastric symptoms, such as epigastiric discomfort, but also extra-gastric sympto...

  3. Gastrointestinal Stromal Tumor: Diagnosis and Prognosis

    International Nuclear Information System (INIS)

    Martin, M. T.; Olmedilla, P.; Gonzalez, S.; Oliver, J. M.

    2003-01-01

    Gastrointestinal stromal tumors (GIST) are mesenquimal tumors derived from cell precursors. They have the capacity for myogenic and neurogenic differentiation and are characterized by expression of KIT protein /tyrosine kinase growth factor). Clinically, they exhibit various biological behaviors. We present 8 cases of GIST, describing both their radiological manifestation through computerized tomography (CT) and most accepted criteria for benignity and malignancy. We also describe the response of one meta statically diagnosed tumor to tyrosine kinase inhibitor. (Author) 9 refs

  4. Course NICER in gastrointestinal and urogenital radiology

    International Nuclear Information System (INIS)

    Aksel Kruse; Nolan, D.J.; Allison, D.J.; Jackson, J.; Gibson, R.

    1998-01-01

    Course of NICER (Nycomed Intercontinental Continuing Education in Radiology) in gastrointestinal and urogenital radiology in the frameworks of NICER program. This program is one of the best educational programs the purpose of which consists in education of maximum good quality, free of marketing and advertisement accessible to roentgenologists of all the countries. The above course was presented in Hua Dong Hospital, Shanghai, China, April 18-21, 1996

  5. Informational needs of gastrointestinal oncology patients.

    Science.gov (United States)

    Papadakos, Janet; Urowitz, Sara; Olmstead, Craig; Jusko Friedman, Audrey; Zhu, Jason; Catton, Pamela

    2015-12-01

    In response to the dearth of consumer health information for patients with gastrointestinal cancers, this study examined the informational needs of these patients to build a plan for future resource development. Although studies have examined informational needs of some such cancers, no published literature has investigated the comprehensive informational needs across all sites of gastrointestinal cancer. A cross-sectional needs assessment comprising a self-administered questionnaire was conducted at an ambulatory gastrointestinal oncology clinic in Toronto, Canada. Patient informational needs were measured, including importance of information, amount desired and preferred mode of delivery. Informational needs were grouped into six domains: medical, practical, physical, emotional, social and spiritual. Eighty-two surveys were analysed. The majority of the respondents were male (53.8%), over the age of 50 (77.8%), and born outside of Canada (51.9%). While many did not speak English as a child (46.3%), and do not speak English at home (22.2%), nearly all indicated comfort with receiving health information in English (97.5%). The majority of respondents were college educated (79.3%) and married (73%). Multiple cancer types were reported; the most common being colorectal (39%), followed by pancreatic (12%) and cancers of the gallbladder or bile duct (12%). Overall, respondents placed highest importance on medical information (P < 0.001). Preferred education modalities were pamphlets, websites and one-on-one discussions with health-care professionals. This study highlights the principal informational needs of patients with gastrointestinal malignancies, along with preferred modality for information delivery. This information will guide the development of educational resources for future patients. © 2014 John Wiley & Sons Ltd.

  6. -Dimensional Fractional Lagrange's Inversion Theorem

    Directory of Open Access Journals (Sweden)

    F. A. Abd El-Salam

    2013-01-01

    Full Text Available Using Riemann-Liouville fractional differential operator, a fractional extension of the Lagrange inversion theorem and related formulas are developed. The required basic definitions, lemmas, and theorems in the fractional calculus are presented. A fractional form of Lagrange's expansion for one implicitly defined independent variable is obtained. Then, a fractional version of Lagrange's expansion in more than one unknown function is generalized. For extending the treatment in higher dimensions, some relevant vectors and tensors definitions and notations are presented. A fractional Taylor expansion of a function of -dimensional polyadics is derived. A fractional -dimensional Lagrange inversion theorem is proved.

  7. Gauge invariant fractional electromagnetic fields

    International Nuclear Information System (INIS)

    Lazo, Matheus Jatkoske

    2011-01-01

    Fractional derivatives and integrations of non-integers orders was introduced more than three centuries ago but only recently gained more attention due to its application on nonlocal phenomenas. In this context, several formulations of fractional electromagnetic fields was proposed, but all these theories suffer from the absence of an effective fractional vector calculus, and in general are non-causal or spatially asymmetric. In order to deal with these difficulties, we propose a spatially symmetric and causal gauge invariant fractional electromagnetic field from a Lagrangian formulation. From our fractional Maxwell's fields arose a definition for the fractional gradient, divergent and curl operators. -- Highlights: → We propose a fractional Lagrangian formulation for fractional Maxwell's fields. → We obtain gauge invariant fractional electromagnetic fields. → Our generalized fractional Maxwell's field is spatially symmetrical. → We discuss the non-causality of the theory.

  8. Gauge invariant fractional electromagnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Lazo, Matheus Jatkoske, E-mail: matheuslazo@furg.br [Instituto de Matematica, Estatistica e Fisica - FURG, Rio Grande, RS (Brazil)

    2011-09-26

    Fractional derivatives and integrations of non-integers orders was introduced more than three centuries ago but only recently gained more attention due to its application on nonlocal phenomenas. In this context, several formulations of fractional electromagnetic fields was proposed, but all these theories suffer from the absence of an effective fractional vector calculus, and in general are non-causal or spatially asymmetric. In order to deal with these difficulties, we propose a spatially symmetric and causal gauge invariant fractional electromagnetic field from a Lagrangian formulation. From our fractional Maxwell's fields arose a definition for the fractional gradient, divergent and curl operators. -- Highlights: → We propose a fractional Lagrangian formulation for fractional Maxwell's fields. → We obtain gauge invariant fractional electromagnetic fields. → Our generalized fractional Maxwell's field is spatially symmetrical. → We discuss the non-causality of the theory.

  9. On matrix fractional differential equations

    Directory of Open Access Journals (Sweden)

    Adem Kılıçman

    2017-01-01

    Full Text Available The aim of this article is to study the matrix fractional differential equations and to find the exact solution for system of matrix fractional differential equations in terms of Riemann–Liouville using Laplace transform method and convolution product to the Riemann–Liouville fractional of matrices. Also, we show the theorem of non-homogeneous matrix fractional partial differential equation with some illustrative examples to demonstrate the effectiveness of the new methodology. The main objective of this article is to discuss the Laplace transform method based on operational matrices of fractional derivatives for solving several kinds of linear fractional differential equations. Moreover, we present the operational matrices of fractional derivatives with Laplace transform in many applications of various engineering systems as control system. We present the analytical technique for solving fractional-order, multi-term fractional differential equation. In other words, we propose an efficient algorithm for solving fractional matrix equation.

  10. Atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Haswell, S.J.

    1991-01-01

    Atomic absorption spectroscopy is now well established and widely used technique for the determination of trace and major elements in a wide range analyte types. There have been many advances in the atomic spectroscopy over the last decade and for this reason and to meet the demand, it was felt that there was a need for an updated book. Whilst interest in instrumental design has tended to dominate the minds of the spectrocopist, the analyst concerned with obtaining reliable and representative data, in diverse areas of application, has been diligently modifying and developing sample treatment and instrumental introduction techniques. Such methodology is de fundamental part of analysis and form the basis of the fourteen application chapters of this book. The text focuses in the main on AAS; however, the sample handling techniques described are in many cases equally applicable to ICP-OES and ICP-MS analysis. (author). refs.; figs.; tabs

  11. Atomic absorption spectrophotometer

    International Nuclear Information System (INIS)

    Stockdale, T. J.

    1985-01-01

    In atomic absorption spectrophotometer, a reference path may be provided for radiation which excludes the flame. This radiation provides a signal from a detector which varies only with the instrumental drift produced by variations in the radiation source brightness and by variations in detector gain. The signal can be used to compensate for drift in other signals received through a sample path including the flame. In the present invention, radiation passes through the sample path continuously during measurement, and only through the reference path between sample measurements. Movable mirrors shift the radiation between the paths upon externally applied commands. Conveniently, the reference path measurement is made while the flame is stabilized during the change between samples. The reference path measurements are stored and used to correct for drift

  12. Analyzing Water's Optical Absorption

    Science.gov (United States)

    2002-01-01

    A cooperative agreement between World Precision Instruments (WPI), Inc., and Stennis Space Center has led the UltraPath(TM) device, which provides a more efficient method for analyzing the optical absorption of water samples at sea. UltraPath is a unique, high-performance absorbance spectrophotometer with user-selectable light path lengths. It is an ideal tool for any study requiring precise and highly sensitive spectroscopic determination of analytes, either in the laboratory or the field. As a low-cost, rugged, and portable system capable of high- sensitivity measurements in widely divergent waters, UltraPath will help scientists examine the role that coastal ocean environments play in the global carbon cycle. UltraPath(TM) is a trademark of World Precision Instruments, Inc. LWCC(TM) is a trademark of World Precision Instruments, Inc.

  13. Transcatheter embolization therapy of the gastrointestinal hemorrhage

    International Nuclear Information System (INIS)

    Sim, Jae In; Park, Auh Whan; Ryeom, Hun Kyu; Kim, Yong Joo

    1994-01-01

    To evaluate the effectiveness of transcatheter embolization for the treatment of massive gastrointestinal arterial bleeding. The study was based on retrospective analysis of twelve cases(8 men, 4 woman) including two patients with hemobilia in which transcatheter embolization was attempted for the control of massive gastrointestinal bleeding from March 1987 to October 1993. Clinical diagnoses of these patients were peptic ulcer(5), pseudoaneurysm formation(3) following percutaneous transhepatic biliary drainage or traffic accident, stomach cancer(1), typhoid fever(1), duodenal leiomyoma(1) and Osler-Weber-Rendu disease (1). Embolized vessels are as follows: gastroduodenal artery(6), left gastric artery(2), ileocolic artery(2), and hepatic artery(2). Embolization was effective in immediate control of bleeding in all patients. Although five of the six patients who had undergone embolization of the gastroduodenal artery developed rebleeding within 24 hour, only 2 required surgery and none showed serious complication. Embolization therapy is safe and effective initial treatment of choice for life-threatening massive gastrointestinal bleeding

  14. Transcatheter embolization therapy of the gastrointestinal hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Jae In; Park, Auh Whan; Ryeom, Hun Kyu; Kim, Yong Joo [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    1994-05-15

    To evaluate the effectiveness of transcatheter embolization for the treatment of massive gastrointestinal arterial bleeding. The study was based on retrospective analysis of twelve cases(8 men, 4 woman) including two patients with hemobilia in which transcatheter embolization was attempted for the control of massive gastrointestinal bleeding from March 1987 to October 1993. Clinical diagnoses of these patients were peptic ulcer(5), pseudoaneurysm formation(3) following percutaneous transhepatic biliary drainage or traffic accident, stomach cancer(1), typhoid fever(1), duodenal leiomyoma(1) and Osler-Weber-Rendu disease (1). Embolized vessels are as follows: gastroduodenal artery(6), left gastric artery(2), ileocolic artery(2), and hepatic artery(2). Embolization was effective in immediate control of bleeding in all patients. Although five of the six patients who had undergone embolization of the gastroduodenal artery developed rebleeding within 24 hour, only 2 required surgery and none showed serious complication. Embolization therapy is safe and effective initial treatment of choice for life-threatening massive gastrointestinal bleeding.

  15. Helical CT in acute lower gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Ernst, Olivier; Leroy, Christophe; Sergent, Geraldine; Bulois, Philippe; Saint-Drenant, Sophie; Paris, Jean-Claude

    2003-01-01

    The purpose of this study was to assess the usefulness of helical CT in depicting the location of acute lower gastrointestinal bleeding. A three-phase helical CT of the abdomen was performed in 24 patients referred for acute lower gastrointestinal bleeding. The diagnosis of the bleeding site was established by CT when there was at least one of the following criteria: spontaneous hyperdensity of the peribowel fat; contrast enhancement of the bowel wall; vascular extravasation of the contrast medium; thickening of the bowel wall; polyp or tumor; or vascular dilation. Diverticula alone were not enough to locate the bleeding site. The results of CT were compared with the diagnosis obtained by colonoscopy, enteroscopy, or surgery. A definite diagnosis was made in 19 patients. The bleeding site was located in the small bowel in 5 patients and the colon in 14 patients. The CT correctly located 4 small bowel hemorrhages and 11 colonic hemorrhages. Diagnosis of the primary lesion responsible for the bleeding was made in 10 patients. Our results suggest that helical CT could be a good diagnostic tool in acute lower gastrointestinal bleeding to help the physician to diagnose the bleeding site. (orig.)

  16. Neonatal gastrointestinal involvement and congenital cytomegalovirus

    Directory of Open Access Journals (Sweden)

    Alessandro Porta

    2016-11-01

    Full Text Available Cytomegalovirus (CMV is the most common cause of congenital viral infection, affecting 0.2 to 2.3% of all live births in developed countries. Very low birth weight and extremely low birth weight newborns are at higher risk of symptomatic CMV infection, most commonly secondary and acquired through breast milk. Gastrointestinal involvement is rare in acquired CMV infections, but it could be an important manifestation of postnatal infection in preterm infants admitted to neonatal intensive care units. Early onset of CMV gastrointestinal signs/symptoms is very rare. In a review of the literature it is described in 5 newborns in the first 24 hours of life, and 6 considering the onset in the first week of life. This review describes also a case report of congenital CMV in an immunocompetent newborn with onset of gastrointestinal signs immediately after birth: a possible association between viral infection and enteric manifestations was considered in the differential diagnosis. A review of the literature of the different case reports found has done, with description and comparison of the different patients and clinical presentations.

  17. Conservative treatment of perforated upper gastrointestinal tract

    International Nuclear Information System (INIS)

    Naoi, Daishi; Sano, Wataru; Nakata, Yasuyuki; Yano, Kentaro; Suzuki, Takeshi; Chiku, Tsuyoshi; Tashiro, Tsuguhiko

    2009-01-01

    In order to clarify the validity of indication criteria of the conservative treatment for perforated upper gastrointestinal tract, a retrospective study was carried out. We enrolled 28 patients with perforation of the gastrointestinal tract who were determined to receive conservative treatment at the time of hospitalization from January 2000 to December 2007. When the following criteria were satisfied, we treated the patients by the conservative treatment after informed consent was gained from them and their families: stable condition of vital signs; peritoneal signs localized in the upper abdomen; and no or slight fluid collection at the Douglas' pouch determined by computed tomography. Patients who showed changes for the worse of peritonitis or increased fluid collection during follow-up were promptly converted to surgery. Six patients were converted to surgery, but all of them were discharged very much improved. We compared patient's data of the conservative treatment group and the converted surgery group at the time of consultation. All data were not statistically different between two groups. If all criteria are satisfied, it seemed that we can start conservative treatment for perforated gastrointestinal tract with careful observation and the system of prompt conversion to operation for patients who showed changes for the worse of peritonitis or increased fluid collection. (author)

  18. Gastrointestinal helminths in raccoons in Texas.

    Science.gov (United States)

    Kresta, Amy E; Henke, Scott E; Pence, Danny B

    2009-01-01

    Raccoons (n=590) were collected from October 1999 to August 2003 from 35 counties across Texas, and gastrointestinal tracts were examined for helminth parasites. Prevalence was calculated and differences in mean abundance were examined among habitat ecoregions, age classes, and between sexes. Twenty different species of helminths (13 nematodes, two cestodes, two acanthocephalans, and three trematodes) were positively identified in the gastrointestinal tracts of 590 raccoons in Texas. Five of the 20 helminth species collected (Physaloptera rara, Placoconus lotoris, Molineus barbatus, Atriotaenia procyonis, and Macracanthorhynchus ingens) had a prevalence >20%. The total number of individuals of these five species (n=22,777) accounted for over 86% of the total number of individuals of all helminth species (n=26,426) collected. Subsequent analyses were based on these five helminths. Mean abundance differed among habitat ecoregions, age classes, and between sexes for all five parasites evaluated. This study is the most comprehensive statewide survey ever done of gastrointestinal helminths of raccoons across Texas. The five most prevalent helminths identified have all been reported in at least one previous survey, indicating that these parasites are not new to Texas and that raccoons are not naïve to the effects these parasites have on them. It may be helpful to wildlife rehabilitators, trappers, wildlife biologists, and other professionals to be aware of parasite abundance in raccoons from different areas of the state, as frequent human-raccoon interactions occur, and some of these parasites could be harmful to humans and domestic animals.

  19. Abdominal imaging findings in gastrointestinal basidiobolomycosis.

    Science.gov (United States)

    Flicek, Kristina T; Vikram, Holenarasipur R; De Petris, Giovanni D; Johnson, C Daniel

    2015-02-01

    To describe the abdominal imaging findings of patients with gastrointestinal Basidiobolus ranarum infection. A literature search was performed to compile the abdominal imaging findings of all reported worldwide cases of gastrointestinal basidiobolomycosis (GIB). In addition, a retrospective review at our institution was performed to identify GIB cases that had imaging findings. A radiologist aware of the diagnosis reviewed the imaging findings in detail. Additional information was obtained from the medical records. A total of 73 GIB cases have been published in the medical literature. The most common abdominal imaging findings were masses in the colon, the liver, or multiple sites and bowel wall thickening. Initially, many patients were considered to have either a neoplasm or Crohn disease. We identified 7 proven cases of GIB at our institution, of which 4 had imaging studies (4 computed tomography [CT] examinations, 4 abdominal radiographs, and an upper gastrointestinal study). Imaging studies showed abnormalities in all 4 cases. Three-fourths of our study patients had an abdominal mass at CT. Two of 3 masses involved the kidneys and included urinary obstruction. All masses showed an inflammatory component with adjacent soft tissue stranding, with or without abscess formation. Radiologists should consider GIB when a patient from an arid climate presents with abdominal pain, weight loss, and an inflammatory abdominal mass on CT. Abdominal masses of the colon or liver, bowel wall thickening, and abscesses are the most common imaging findings.

  20. Yttrium-90 microsphere induced gastrointestinal tract ulceration

    Directory of Open Access Journals (Sweden)

    Rikabi Ali A

    2008-09-01

    Full Text Available Abstract Background Radiomicrosphere therapy (RT utilizing yttrium-90 (90Y microspheres has been shown to be an effective regional treatment for primary and secondary hepatic malignancies. We sought to determine a large academic institution's experience regarding the extent and frequency of gastrointestinal complications. Methods Between 2004 and 2007, 27 patients underwent RT for primary or secondary hepatic malignancies. Charts were subsequently reviewed to determine the incidence and severity of GI ulceration. Results Three patients presented with gastrointestinal bleeding and underwent upper endoscopy. Review of the pretreatment angiograms showed normal vascular anatomy in one patient, sclerosed hepatic vasculature in a patient who had undergone prior chemoembolization in a second, and an aberrant left hepatic artery in a third. None had undergone prophylactic gastroduodenal artery embolization. Endoscopic findings included erythema, mucosal erosions, and large gastric ulcers. Microspheres were visible on endoscopic biopsy. In two patients, gastric ulcers were persistent at the time of repeat endoscopy 1–4 months later despite proton pump inhibitor therapy. One elderly patient who refused surgical intervention died from recurrent hemorrhage. Conclusion Gastrointestinal ulceration is a known yet rarely reported complication of 90Y microsphere embolization with potentially life-threatening consequences. Once diagnosed, refractory ulcers should be considered for aggressive surgical management.

  1. Mechanistic Oral Absorption Modeling and Simulation for Formulation Development and Bioequivalence Evaluation: Report of an FDA Public Workshop.

    Science.gov (United States)

    Zhang, X; Duan, J; Kesisoglou, F; Novakovic, J; Amidon, G L; Jamei, M; Lukacova, V; Eissing, T; Tsakalozou, E; Zhao, L; Lionberger, R

    2017-08-01

    On May 19, 2016, the US Food and Drug Administration (FDA) hosted a public workshop, entitled "Mechanistic Oral Absorption Modeling and Simulation for Formulation Development and Bioequivalence Evaluation." The topic of mechanistic oral absorption modeling, which is one of the major applications of physiologically based pharmacokinetic (PBPK) modeling and simulation, focuses on predicting oral absorption by mechanistically integrating gastrointestinal transit, dissolution, and permeation processes, incorporating systems, active pharmaceutical ingredient (API), and the drug product information, into a systemic mathematical whole-body framework. © 2017 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

  2. Intestinal absorption and retention of cadmium in neonatal pigs compared to rats and guinea pigs

    International Nuclear Information System (INIS)

    Sasser, L.B.; Jarboe, G.E.

    1980-01-01

    The purpose of this study was to measure intestinal absorption and retention of cadmium in the newborn pig and to compare data from the pig, rat and guinea pig, three species that differ greatly in their ability to absorb macromolecules at birth. Newborn pigs were administered a single oral dose of 50 μCi of /sup 115m/Cd 24 hours after birth and killed at intervals between 1 and 14 days after dosing. Cd absorption and gastrointestinal retention were then determined; these data were compared with similar data from the rat and guinea pig. Cd absorption in the neonate appears to be a two-step process; mucosal uptake of Cd from the lumen, probably by pinocytosis, followed by transfer of a portion of this Cd into the body. This transfer process is similar, but does not entirely coincide with changes associated with protein absorption in the neonate

  3. Extraordinary absorption of sound in porous lamella-crystals

    DEFF Research Database (Denmark)

    Christensen, Johan; Romero-García, V.; Picó, R.

    2014-01-01

    . Experimental measurements show that strong all-angle sound absorption with almost zero reflectance takes place for a frequency range exceeding two octaves. We demonstrate that lowering the crystal filling fraction increases the wave interaction time and is responsible for the enhancement of intrinsic material......We present the design of a structured material supporting complete absorption of sound with a broadband response and functional for any direction of incident radiation. The structure which is fabricated out of porous lamellas is arranged into a low-density crystal and backed by a reflecting support...

  4. The Local Fractional Bootstrap

    DEFF Research Database (Denmark)

    Bennedsen, Mikkel; Hounyo, Ulrich; Lunde, Asger

    We introduce a bootstrap procedure for high-frequency statistics of Brownian semistationary processes. More specifically, we focus on a hypothesis test on the roughness of sample paths of Brownian semistationary processes, which uses an estimator based on a ratio of realized power variations. Our...... new resampling method, the local fractional bootstrap, relies on simulating an auxiliary fractional Brownian motion that mimics the fine properties of high frequency differences of the Brownian semistationary process under the null hypothesis. We prove the first order validity of the bootstrap method...... and in simulations we observe that the bootstrap-based hypothesis test provides considerable finite-sample improvements over an existing test that is based on a central limit theorem. This is important when studying the roughness properties of time series data; we illustrate this by applying the bootstrap method...

  5. Fractionalization and Entrepreneurial Activities

    OpenAIRE

    Awaworyi Churchill, Sefa

    2015-01-01

    The vast majority of the literature on ethnicity and entrepreneurship focuses on the construct of ethnic entrepreneurship. However, very little is known about how ethnic heterogeneity affects entrepreneurship. This study attempts to fill the gap, and thus examines the effect of ethnic heterogeneity on entrepreneurial activities in a cross-section of 90 countries. Using indices of ethnic and linguistic fractionalization, we show that ethnic heterogeneity negatively influences entrepreneurship....

  6. Atomic absorption spectrophotometry in perspective

    International Nuclear Information System (INIS)

    Soffiantini, V.

    1981-01-01

    Atomic absorption spectrophotometry is essentially an analytical technique used for quantitative trace metal analysis in a variety of materials. The speed and specificity of the technique is its greatest advantage over other analytical techniques. What atomic absorption spectrophotometry can and cannot do and its advantages and disadvantages are discussed, a summary of operating instructions are given, as well as a summary of analytical interferences. The applications of atomic absorption spectrophotometry are also shortly discussed

  7. Nonlinear effects in collective absorption

    International Nuclear Information System (INIS)

    Uenoyama, Takeshi; Mima, Kunioki; Watanabe, Tsuguhiro.

    1981-01-01

    The collective absorption of high intensity laser radiation is analyzed numerically. Density profile modification due to the ponderomotive force associating laser radiation and the excited electron plasma waves is self-consistently taken into account, and the intensity dependences of the absorption efficiency are obtained. In the high intensity regime, the absorption efficiency is found to be strongly enhanced in the plasma without flow, but reduced with supersonic flow. (author)

  8. Vitamin B12 absorption capacity in healthy children

    International Nuclear Information System (INIS)

    Hjelt, K.; Krasilnikoff, P.A.

    1986-01-01

    B12 absorption was investigated in 47 healthy children aged 7 months to 15.8 years (median 4.9 years). The patients had either recovered from giardiasis, the post-gastroenteritis syndrome, or had celiac disease in remission (treated with a gluten-free diet). The B12 absorption was measured by a double-isotope technique using 57 CoB12 and 51 CrCl 3 , the latter being the inabsorbable marker. The radiation dose was minimal. The results were presented as fractional absorption of B12 (FAB12). Within the different age groups, the absorption test was performed by means of the following oral amounts of B12: 0- less than 1 year, 0.5 microgram; 1-3 years: 1.7 micrograms, 4-6 years, 2.5 micrograms; 7-10 years; 3.3 micrograms; and 11-15 years, 4.5 micrograms. When using these oral amounts of B12, the medians (and ranges) of FAB12 were found to be: 1-3 years (n = 18), 37% (16-80%); 4-6 years (n = 10), 27% (19-40%); 7-10 years (n = 9), 32% (21-44%); and 11-15 years (n = 8), 27% (19-59%). The FAB12 in two children aged 7 and 11 months was 31% and 32%, respectively. These results may be interpretated as reference values for B12 absorption in children. Further absorption tests were performed in seven children representing the four age groups from 1 to 15 years. When a high oral amount of B12 was given (i.e., three times the saturation dose), the FAB12 ranged from 0 to 20% (median 9%), whereas a low amount (i.e., one-ninth of the saturation dose) produced fractional absorptions from 65 to 82% (median 74%)

  9. Scramjet Performance Assessment Using Water Absorption Diagnostics (U)

    Science.gov (United States)

    Cavolowsky, John A.; Loomis, Mark P.; Deiwert, George

    1995-01-01

    Simultaneous multiple path measurements of temperature and H2O concentration will be presented for the AIMHYE test entries in the NASA Ames 16-Inch Shock Tunnel. Monitoring the progress of high temperature chemical reactions that define scramjet combustor efficiencies is a task uniquely suited to nonintrusive optical diagnostics. One application strategy to overcome the many challenges and limitations of nonintrusive measurements is to use laser absorption spectroscopy coupled with optical fibers. Absorption spectroscopic techniques with rapidly tunable lasers are capable of making simultaneous measurements of mole fraction, temperature, pressure, and velocity. The scramjet water absorption diagnostic was used to measure combustor efficiency and was compared to thrust measurements using a nozzle force balance and integrated nozzle pressures to develop a direct technique for evaluating integrated scramjet performance. Tests were initially performed with a diode laser tuning over a water absorption feature at 1391.7 nm. A second diode laser later became available at a wavelength near 1343.3 nm covering an additional water absorption feature and was incorporated in the system for a two-wavelength technique. Both temperature and mole fraction can be inferred from the lineshape analysis using this approach. Additional high temperature spectroscopy research was conducted to reduce uncertainties in the scramjet application. The lasers are optical fiber coupled to ports at the combustor exit and in the nozzle region. The output from the two diode lasers were combined in a single fiber, and the resultant two-wavelength beam was subsequently split into four legs. Each leg was directed through 60 meters of optical fiber to four combustor exit locations for measurement of beam intensity after absorption by the water within the flow. Absorption results will be compared to 1D combustor analysis using RJPA and nozzle CFD computations as well as to data from a nozzle metric

  10. Vitamin B12 absorption capacity in healthy children

    Energy Technology Data Exchange (ETDEWEB)

    Hjelt, K.; Krasilnikoff, P.A.

    1986-03-01

    B12 absorption was investigated in 47 healthy children aged 7 months to 15.8 years (median 4.9 years). The patients had either recovered from giardiasis, the post-gastroenteritis syndrome, or had celiac disease in remission (treated with a gluten-free diet). The B12 absorption was measured by a double-isotope technique using /sup 57/CoB12 and /sup 51/CrCl/sub 3/, the latter being the inabsorbable marker. The radiation dose was minimal. The results were presented as fractional absorption of B12 (FAB12). Within the different age groups, the absorption test was performed by means of the following oral amounts of B12: 0- less than 1 year, 0.5 microgram; 1-3 years: 1.7 micrograms, 4-6 years, 2.5 micrograms; 7-10 years; 3.3 micrograms; and 11-15 years, 4.5 micrograms. When using these oral amounts of B12, the medians (and ranges) of FAB12 were found to be: 1-3 years (n = 18), 37% (16-80%); 4-6 years (n = 10), 27% (19-40%); 7-10 years (n = 9), 32% (21-44%); and 11-15 years (n = 8), 27% (19-59%). The FAB12 in two children aged 7 and 11 months was 31% and 32%, respectively. These results may be interpretated as reference values for B12 absorption in children. Further absorption tests were performed in seven children representing the four age groups from 1 to 15 years. When a high oral amount of B12 was given (i.e., three times the saturation dose), the FAB12 ranged from 0 to 20% (median 9%), whereas a low amount (i.e., one-ninth of the saturation dose) produced fractional absorptions from 65 to 82% (median 74%).

  11. Fractional Number Operator and Associated Fractional Diffusion Equations

    Science.gov (United States)

    Rguigui, Hafedh

    2018-03-01

    In this paper, we study the fractional number operator as an analog of the finite-dimensional fractional Laplacian. An important relation with the Ornstein-Uhlenbeck process is given. Using a semigroup approach, the solution of the Cauchy problem associated to the fractional number operator is presented. By means of the Mittag-Leffler function and the Laplace transform, we give the solution of the Caputo time fractional diffusion equation and Riemann-Liouville time fractional diffusion equation in infinite dimensions associated to the fractional number operator.

  12. X-ray Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yano, Junko; Yachandra, Vittal K.

    2009-07-09

    This review gives a brief description of the theory and application of X-ray absorption spectroscopy, both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), especially, pertaining to photosynthesis. The advantages and limitations of the methods are discussed. Recent advances in extended EXAFS and polarized EXAFS using oriented membranes and single crystals are explained. Developments in theory in understanding the XANES spectra are described. The application of X-ray absorption spectroscopy to the study of the Mn4Ca cluster in Photosystem II is presented.

  13. The role of endoscopy in pediatric gastrointestinal bleeding

    Science.gov (United States)

    Franke, Markus; Geiß, Andrea; Greiner, Peter; Wellner, Ulrich; Richter-Schrag, Hans-Jürgen; Bausch, Dirk; Fischer, Andreas

    2016-01-01

    Background and study aims: Gastrointestinal bleeding in children and adolescents accounts for up to 20 % of referrals to gastroenterologists. Detailed management guidelines exist for gastrointestinal bleeding in adults, but they do not encompass children and adolescents. The aim of this study was to assess gastrointestinal bleeding in pediatric patients and to determine an investigative management algorithm accounting for the specifics of children and adolescents. Patients and methods: Pediatric patients with gastrointestinal bleeding admitted to our endoscopy unit from 2001 to 2009 (n = 154) were identified. Retrospective statistical and neural network analysis was used to assess outcome and to determine an investigative management algorithm. Results: The source of bleeding could be identified in 81 % (n = 124/154). Gastrointestinal bleeding was predominantly lower gastrointestinal bleeding (66 %, n = 101); upper gastrointestinal bleeding was much less common (14 %, n = 21). Hematochezia was observed in 94 % of the patients with lower gastrointestinal bleeding (n = 95 of 101). Hematemesis (67 %, n = 14 of 21) and melena (48 %, n = 10 of 21) were associated with upper gastrointestinal bleeding. The sensitivity and specificity of a neural network to predict lower gastrointestinal bleeding were 98 % and 63.6 %, respectively and to predict upper gastrointestinal bleeding were 75 % and 96 % respectively. The sensitivity and specifity of hematochezia alone to predict lower gastrointestinal bleeding were 94.2 % and 85.7 %, respectively. The sensitivity and specificity for hematemesis and melena to predict upper gastrointestinal bleeding were 82.6 % and 94 %, respectively. We then developed an investigative management algorithm based on the presence of hematochezia and hematemesis or melena. Conclusions: Hematochezia should prompt colonoscopy and hematemesis or melena should prompt esophagogastroduodenoscopy. If no

  14. Gastrointestinal and renal responses to variable water intake in whitebellied sunbirds and New Holland honeyeaters.

    Science.gov (United States)

    Purchase, Cromwell; Napier, Kathryn R; Nicolson, Susan W; McWhorter, Todd J; Fleming, Patricia A

    2013-05-01

    Nectarivores face a constant challenge in terms of water balance, experiencing water loading or dehydration when switching between food plants or between feeding and fasting. To understand how whitebellied sunbirds and New Holland honeyeaters meet the challenges of varying preformed water load, we used the elimination of intramuscular-injected [(14)C]-l-glucose and (3)H2O to quantify intestinal and renal water handling on diets varying in sugar concentration. Both sunbirds and honeyeaters showed significant modulation of intestinal water absorption, allowing excess water to be shunted through the intestine when on dilute diets. Despite reducing their fractional water absorption, both species showed linear increases in water flux and fractional body water turnover as water intake increased (both afternoon and morning), suggesting that the modulation of fractional water absorption was not sufficient to completely offset dietary water loads. In both species, glomerular filtration rate was independent of water gain (but was higher for the afternoon), as was renal fractional water reabsorption (measured in the afternoon). During the natural overnight fast, both sunbirds and honeyeaters arrested whole kidney function. Evaporative water loss in sunbirds was variable but correlated with water gain. Both sunbirds and honeyeaters appear to modulate intestinal water absorption as an important component of water regulation to help deal with massive preformed water loads. Shutting down glomerular filtration rate during the overnight fast is another way of saving energy for osmoregulatory function. Birds maintain osmotic balance on diets varying markedly in preformed water load by varying both intestinal water absorption and excretion through the intestine and kidneys.

  15. Galactic absorption line coronae

    International Nuclear Information System (INIS)

    Bregman, J.N.

    1981-01-01

    We have investigated whether gaseous coronae around galaxies rise to the absorption systems seen in quasar spectra. In our model, gas originally located in the disk is heated to the million degree range and rises to surround the galaxy; the gas remains bound to the galaxy. Optically thin radiative cooling drives a thermal instability in the hot gas which causes cool clouds (T 4 K) to condense out of the corona. These clouds, which follow ballistic trajectories back to the disk, are the absorption sites. A two-dimensional hydrodynamic code with radiative cooling was used to study the dynamics and thermodynamics of the corona as well as the position rate at which clouds form. Coupled to the code is a galaxy with two mass components, a disk (approx.10 11 M/sub sun/) and a dark halo (approx.10 12 M/sub sun/). In a model where the temperature at the base of the corona (in the disk) is 3 x 10 6 K, absorbing gas of column density NL> or approx. =10 18 cm 2 extends radially to 100 kpc (face-on orientation) and vertically to 60 Kpc (edge-on orientation). The total mass of gas required here (coronal plus cloud gas) is 1.4 x 10 10 M/sub sun/, while the minimum supernova heating rate is one supernova per 27 years. In two other models (base coronal temperatures of 0.50 x 10 6 K and 1 x 10 6 K), coronal gas rises from an extended gaseous disk (in the previous model, the gas comes from a typical gaseous disk approximately 15 kpc in extent). Here, column densities of 10 19 cm -2 out to a radius of 70 kpc (face-on orientation) are achieved with a total gas mass of 1.7 x 10 9 M/sub direct-product/ and 2.0 x 10 9 M/sub sun/ and minimum heating rates of approximately one supernova per 170 years and one supernova per 60 years

  16. Immunomodulatory potential of a brewers' spent grain protein hydrolysate incorporated into low-fat milk following in vitro gastrointestinal digestion.

    Science.gov (United States)

    Crowley, Damian; O'Callaghan, Yvonne; McCarthy, Aoife; Connolly, Alan; Piggott, Charles O; FitzGerald, Richard J; O'Brien, Nora M

    2015-01-01

    Brewers' spent grain (BSG) protein rich fraction was previously hydrolysed using Alcalase (U) and three additional fractions were prepared by membrane fractionation; a 5-kDa retentate (U > 5), a 5-kDa permeate (U milk, subjected to simulated gastrointestinal digestion (SGID) and their anti-inflammatory potential was investigated. The digestates caused a significant reduction (p RAW 264.7 cells. IL-2 and interferon-γ (IFN-γ) production in stimulated Jurkat T cells and IL-1β and tumor necrosis factor-α (TNF-α) production in stimulated RAW 264.7 cells were not affected in the presence of the digestates. Results show that a SGID milk product supplemented with BSG hydrolysate and its associated ultrafiltered fractions can confer anti-inflammatory effects in Jurkat T cells.

  17. Gauge invariant fractional electromagnetic fields

    Science.gov (United States)

    Lazo, Matheus Jatkoske

    2011-09-01

    Fractional derivatives and integrations of non-integers orders was introduced more than three centuries ago but only recently gained more attention due to its application on nonlocal phenomenas. In this context, several formulations of fractional electromagnetic fields was proposed, but all these theories suffer from the absence of an effective fractional vector calculus, and in general are non-causal or spatially asymmetric. In order to deal with these difficulties, we propose a spatially symmetric and causal gauge invariant fractional electromagnetic field from a Lagrangian formulation. From our fractional Maxwell's fields arose a definition for the fractional gradient, divergent and curl operators.

  18. Artificial Lipid Membrane Permeability Method for Predicting Intestinal Drug Transport: Probing the Determining Step in the Oral Absorption of Sulfadiazine; Influence of the Formation of Binary and Ternary Complexes with Cyclodextrins.

    Science.gov (United States)

    Delrivo, Alicia; Aloisio, Carolina; Longhi, Marcela R; Granero, Gladys

    2018-04-01

    We propose an in vitro permeability assay by using a modified lipid membrane to predict the in vivo intestinal passive permeability of drugs. Two conditions were tested, one with a gradient pH (pH 5.5 donor/pH 7.4 receptor) and the other with an iso-pH 7.4. The predictability of the method was established by correlating the obtained apparent intestinal permeability coefficients (P app ) and the oral dose fraction absorbed in humans (f a ) of 16 drugs with different absorption properties. The P app values correlated well with the absorption rates under the two conditions, and the method showed high predictability and good reproducibility. On the other hand, with this method, we successfully predicted the transport characteristics of oral sulfadiazine (SDZ). Also, the tradeoff between the increase in the solubility of SDZ by its complex formation with cyclodextrins and/or aminoacids and its oral permeability was assessed. Results suggest that SDZ is transported through the gastrointestinal epithelium by passive diffusion in a pH-dependent manner. These results support the classification of SDZ as a high/low borderline permeability compound and are in agreement with the Biopharmaceutics Classification Systems (BCS). This conclusion is consistent with the in vivo pharmacokinetic properties of SDZ.

  19. Human Nanog pseudogene8 promotes the proliferation of gastrointestinal cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, Keita, E-mail: uchino13@intmed1.med.kyushu-u.ac.jp [Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Hirano, Gen [Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Hirahashi, Minako [Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Isobe, Taichi; Shirakawa, Tsuyoshi; Kusaba, Hitoshi; Baba, Eishi [Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Tsuneyoshi, Masazumi [Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Akashi, Koichi [Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)

    2012-09-10

    There is emerging evidence that human solid tumor cells originate from cancer stem cells (CSCs). In cancer cell lines, tumor-initiating CSCs are mainly found in the side population (SP) that has the capacity to extrude dyes such as Hoechst 33342. We found that Nanog is expressed specifically in SP cells of human gastrointestinal (GI) cancer cells. Nucleotide sequencing revealed that NanogP8 but not Nanog was expressed in GI cancer cells. Transfection of NanogP8 into GI cancer cell lines promoted cell proliferation, while its inhibition by anti-Nanog siRNA suppressed the proliferation. Immunohistochemical staining of primary GI cancer tissues revealed NanogP8 protein to be strongly expressed in 3 out of 60 cases. In these cases, NanogP8 was found especially in an infiltrative part of the tumor, in proliferating cells with Ki67 expression. These data suggest that NanogP8 is involved in GI cancer development in a fraction of patients, in whom it presumably acts by supporting CSC proliferation. -- Highlights: Black-Right-Pointing-Pointer Nanog maintains pluripotency by regulating embryonic stem cells differentiation. Black-Right-Pointing-Pointer Nanog is expressed in cancer stem cells of human gastrointestinal cancer cells. Black-Right-Pointing-Pointer Nucleotide sequencing revealed that Nanog pseudogene8 but not Nanog was expressed. Black-Right-Pointing-Pointer Nanog pseudogene8 promotes cancer stem cells proliferation. Black-Right-Pointing-Pointer Nanog pseudogene8 is involved in gastrointestinal cancer development.

  20. Human Nanog pseudogene8 promotes the proliferation of gastrointestinal cancer cells

    International Nuclear Information System (INIS)

    Uchino, Keita; Hirano, Gen; Hirahashi, Minako; Isobe, Taichi; Shirakawa, Tsuyoshi; Kusaba, Hitoshi; Baba, Eishi; Tsuneyoshi, Masazumi; Akashi, Koichi

    2012-01-01

    There is emerging evidence that human solid tumor cells originate from cancer stem cells (CSCs). In cancer cell lines, tumor-initiating CSCs are mainly found in the side population (SP) that has the capacity to extrude dyes such as Hoechst 33342. We found that Nanog is expressed specifically in SP cells of human gastrointestinal (GI) cancer cells. Nucleotide sequencing revealed that NanogP8 but not Nanog was expressed in GI cancer cells. Transfection of NanogP8 into GI cancer cell lines promoted cell proliferation, while its inhibition by anti-Nanog siRNA suppressed the proliferation. Immunohistochemical staining of primary GI cancer tissues revealed NanogP8 protein to be strongly expressed in 3 out of 60 cases. In these cases, NanogP8 was found especially in an infiltrative part of the tumor, in proliferating cells with Ki67 expression. These data suggest that NanogP8 is involved in GI cancer development in a fraction of patients, in whom it presumably acts by supporting CSC proliferation. -- Highlights: ► Nanog maintains pluripotency by regulating embryonic stem cells differentiation. ► Nanog is expressed in cancer stem cells of human gastrointestinal cancer cells. ► Nucleotide sequencing revealed that Nanog pseudogene8 but not Nanog was expressed. ► Nanog pseudogene8 promotes cancer stem cells proliferation. ► Nanog pseudogene8 is involved in gastrointestinal cancer development.

  1. The Extended Fractional Subequation Method for Nonlinear Fractional Differential Equations

    OpenAIRE

    Zhao, Jianping; Tang, Bo; Kumar, Sunil; Hou, Yanren

    2012-01-01

    An extended fractional subequation method is proposed for solving fractional differential equations by introducing a new general ansätz and Bäcklund transformation of the fractional Riccati equation with known solutions. Being concise and straightforward, this method is applied to the space-time fractional coupled Burgers’ equations and coupled MKdV equations. As a result, many exact solutions are obtained. It is shown that the considered method provides a very effective, convenient, and powe...

  2. Absorption, transport, and chemical fate of plutonium in soybean plants

    International Nuclear Information System (INIS)

    Garland, T.R.; Cataldo, D.A.; Wildung, R.E.

    1981-01-01

    Absorption of plutonium (Pu) by soybean plants (Glycine max cv. Williams) is limited by Pu solubility in soils. Changes in Pu concentration in different tissues with time to senescence indicate Pu is freely transported through the xylem during growth but not subject to remobilization on flowering. Studies in which the DTPA complex of 238 Pu was supplied to the plant suggest a change in chemical form following root absorption. Of the Pu in roots, stems, and leaves at senescence, 28, 54, and 67%, respectively, were soluble. The Pu in the solluble fraction was primarily associated with components of >10000 equivalent molecular weight in leaves and roots, whereas stems exhibited an equal distribution between components in the >10000 and <500 molecular weight fractions. Plutonium associated with mature seeds is concentrated in the seed hull (85%) and cotyledons (14%). The Pu associated with the cotyledon was primarily in the insoluble residues and soluble soy whey

  3. Identification of New Anti-inflammatory Peptides from Zein Hydrolysate after Simulated Gastrointestinal Digestion and Transport in Caco-2 Cells.

    Science.gov (United States)

    Liang, Qiufang; Chalamaiah, Meram; Ren, Xiaofeng; Ma, Haile; Wu, Jianping

    2018-02-07

    Chronic inflammation is an underlying contributor to various chronic diseases. The objectives of this study were to investigate the anti-inflammatory activity of zein hydrolysate after simulated gastrointestinal digestion and Caco-2 cell absorption and to identify novel anti-inflammatory peptides after transport across Caco-2 cells. Three zein hydrolysates were prepared and further digested using gastrointestinal proteases; their transports were studied in Caco-2 cells. Anti-inflammatory activity was studied in endothelial EA.hy926 cells. Three zein hydrolysates and their digests significantly decreased the expression of tumor necrosis factor-α (TNF-α) induced pro-inflammatory vascular cell adhesion molecule-1 (VCAM-1) by 37.3-66.0%. Eleven novel peptides with 5-9 amino acid residues were sequenced; three peptides showed strong anti-inflammatory activity by inhibiting the VCAM-1 by 54-38.9% and intercellular cell adhesion molecule-1 (ICAM-1) by 36.5-28.6% at 0.2 mM. A new approach to identify novel anti-inflammatory peptides that could survive gastrointestinal digestion and absorption was developed.

  4. Functional Fractional Calculus

    CERN Document Server

    Das, Shantanu

    2011-01-01

    When a new extraordinary and outstanding theory is stated, it has to face criticism and skeptism, because it is beyond the usual concept. The fractional calculus though not new, was not discussed or developed for a long time, particularly for lack of its application to real life problems. It is extraordinary because it does not deal with 'ordinary' differential calculus. It is outstanding because it can now be applied to situations where existing theories fail to give satisfactory results. In this book not only mathematical abstractions are discussed in a lucid manner, with physical mathematic

  5. Fractional Reserve Banking

    OpenAIRE

    Andreasen, Niels; Bjerregaard, Mads; Lund, Jonas; Olsen, Ove Bitsch; Rasmussen, Andreas Dalgas

    2012-01-01

    Projektet er bygget op omkring kritisk realisme, som er det gennemgående videnskabelige fundament til undersøgelsen af hvilke strukturelle grunde der er til finansiel ustabilitet i Danmark. Projektet går i dybden med Fractional Reserve Banking og incitamentsstrukturen i banksystemet. Vi bevæger os både på det makro- og mikroøkonomiske niveau i analysen. På makro niveau bruger vi den østrigske skole om konjunktur teori (The Positive Theory of the Cycle). På mikro niveau arbejder vi med princip...

  6. Plasma fractionation issues.

    Science.gov (United States)

    Farrugia, Albert; Evers, Theo; Falcou, Pierre-Francois; Burnouf, Thierry; Amorim, Luiz; Thomas, Sylvia

    2009-04-01

    Procurement and processing of human plasma for fractionation of therapeutic proteins or biological medicines used in clinical practice is a multi-billion dollar international trade. Together the private sector and public sector (non-profit) provide large amounts of safe and effective therapeutic plasma proteins needed worldwide. The principal therapeutic proteins produced by the dichotomous industry include gamma globulins or immunoglobulins (including pathogen-specific hyperimmune globulins, such as hepatitis B immune globulins) albumin, factor VIII and Factor IX concentrates. Viral inactivation, principally by solvent detergent and other processes, has proven highly effective in preventing transmission of enveloped viruses, viz. HBV, HIV, and HCV.

  7. Wave energy absorption by ducks

    OpenAIRE

    Kurniawan, Adi

    2017-01-01

    We study the absorption of wave energy by a single and multiple cam-shaped bodies referred to as ducks. Numerical models are developed under the assumptions of linear theory. We consider wave absorption by a single duck as well as by two lines of ducks meeting at an angle.

  8. Wave energy absorption by ducks

    DEFF Research Database (Denmark)

    Kurniawan, Adi

    2018-01-01

    We study the absorption of wave energy by a single and multiple cam-shaped bodies referred to as ducks. Numerical models are developed under the assumptions of linear theory. We consider wave absorption by a single duck as well as by two lines of ducks meeting at an angle....

  9. Atomic absorption instrument functional description

    International Nuclear Information System (INIS)

    Bystroff, R.I.; Boyle, W.G. Jr.; Barton, G.W. Jr.

    1976-01-01

    This report describes a proposed system for automating atomic absorption analysis. The system consists of two atomic absorption instruments and an automatic sampler that can be attached to either instrument. A computer program controls the sampling and gathers data. The program then uses the data to perform bookkeeping, data processing, and report writing

  10. Sublinear absorption in OCS gas

    International Nuclear Information System (INIS)

    Bogani, F.; Querzoli, R.; Ernst, K.

    1988-01-01

    Sublinear absorption in OCS gas has been experimentally studied in detail by means of an optoacustic technique and transmission measurements. The best fit of the results is obtained by a phenomenological model, that considers the process as the sum of one-and two-photon absorptions

  11. Optical absorption of irradiated carbohydrates

    International Nuclear Information System (INIS)

    Supe, A.A.; Tiliks, Yu.E.

    1994-01-01

    The optical absorption spectra of γ-irradiated carbohydrates (glucose, lactose, sucrose, maltose, and starch) and their aqueous solutions were studied. The comparison of the data obtained with the determination of the concentrations of molecular and radical products of radiolysis allows the absorption bands with maxima at 250 and 310 nm to be assigned to the radicals trapped in the irradiated carbohydrates

  12. Water absorption in brick masonry

    NARCIS (Netherlands)

    Brocken, H.J.P.; Smolders, H.R.

    1996-01-01

    The water absorption in brick, mortar that was cured separately, and masonry samples was studied using NMR. Models of the moisture transport are usually formulated on the basis of a diffusion equation. In the case of water absorption in separate brick and mortar samples, the moisture diffusivity in

  13. Subgap absorption in conjugated polymers

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, M.; Seager, C.H. (Sandia National Labs., Albuquerque, NM (USA)); McBranch, D.; Heeger, A.J. (California Univ., Santa Barbara, CA (USA)); Baker, G.L. (Bell Communications Research, Inc., Red Bank, NJ (USA))

    1991-01-01

    Along with X{sup (3)}, the magnitude of the optical absorption in the transparent window below the principal absorption edge is an important parameter which will ultimately determine the utility of conjugated polymers in active integrated optical devices. With an absorptance sensitivity of < 10{sup {minus}5}, Photothermal Deflection Spectroscopy (PDS) is ideal for determining the absorption coefficients of thin films of transparent'' materials. We have used PDS to measure the optical absorption spectra of the conjugated polymers poly(1,4-phenylene-vinylene) (and derivitives) and polydiacetylene-4BCMU in the spectral region from 0.55 eV to 3 eV. Our spectra show that the shape of the absorption edge varies considerably from polymer to polymer, with polydiacetylene-4BCMU having the steepest absorption edge. The minimum absorption coefficients measured varied somewhat with sample age and quality, but were typically in the range 1 cm{sup {minus}1} to 10 cm{sup {minus}1}. In the region below 1 eV, overtones of C-H stretching modes were observed, indicating that further improvements in transparency in this spectral region might be achieved via deuteration of fluorination. 11 refs., 4 figs.

  14. Multifunctional hybrids for electromagnetic absorption

    International Nuclear Information System (INIS)

    Huynen, I.; Quievy, N.; Bailly, C.; Bollen, P.; Detrembleur, C.; Eggermont, S.; Molenberg, I.; Thomassin, J.M.; Urbanczyk, L.

    2011-01-01

    Highlights: → EM absorption requires low dielectric constant and ∼1 S/m electrical conductivity. → New hybrids were processed with CNT-filled polymer foam inserted in Al honeycomb. → The EM absorption in the GHz range is superior to any known material. → A closed form model is used to guide the design of the hybrid. → The architectured material is light with potential for thermal management. - Abstract: Electromagnetic (EM) interferences are ubiquitous in modern technologies and impact on the reliability of electronic devices and on living cells. Shielding by EM absorption, which is preferable over reflection in certain instances, requires combining a low dielectric constant with high electrical conductivity, which are antagonist properties in the world of materials. A novel class of hybrid materials for EM absorption in the gigahertz range has been developed based on a hierarchical architecture involving a metallic honeycomb filled with a carbon nanotube-reinforced polymer foam. The waveguide characteristics of the honeycomb combined with the performance of the foam lead to unexpectedly large EM power absorption over a wide frequency range, superior to any known material. The peak absorption frequency can be tuned by varying the shape of the honeycomb unit cell. A closed form model of the EM reflection and absorption provides a tool for the optimization of the hybrid. This designed material sets the stage for a new class of sandwich panels combining high EM absorption with mass efficiency, stiffness and thermal management.

  15. Sonographic features of gastrointestinal lymphoma in 15 dogs.

    Science.gov (United States)

    Frances, M; Lane, A E; Lenard, Z M

    2013-09-01

    The purpose of this study is to describe the sonographic appearance of lymphoma of the gastrointestinal tract in dogs. A retrospective review was conducted and patients with gastrointestinal lymphoma diagnosed by histopathology (including immunohistochemistry, where available) or cytology that had an abdominal ultrasound were included. Four of 15 (26·7%) cases with histopathologically confirmed lymphoma exhibited no sonographic abnormalities. In the dogs with sonographic abnormalities, features including intestinal wall thickness and the presence or absence of wall layering were highly variable. Clinical signs pertaining to the gastrointestinal tract were also unreliable markers of gastrointestinal lymphoma, with weight loss, vomiting, and diarrhoea being uncommon presenting complaints; intestinal obstruction was not present in any patient. The sonographic appearance of gastrointestinal lymphoma in dogs is non-specific. Gastrointestinal lymphoma in dogs should be maintained as a differential diagnosis despite a sonographically normal appearing bowel. © 2013 British Small Animal Veterinary Association.

  16. Roles and Regulation of Gastrointestinal Eosinophils in Immunity and Disease

    Science.gov (United States)

    Jung, YunJae; Rothenberg, Marc E.

    2014-01-01

    Eosinophils have been considered to be destructive end-stage effector cells that have a role in parasitic infections and allergy reactions by the release of their granule-derived cytotoxic proteins. However, an increasing number of experimental observations indicate that eosinophils also are multifunctional leukocytes involved in diverse inflammatory and physiologic immune responses. Under homeostatic conditions, eosinophils are particularly abundant in the lamina propria of the gastrointestinal tract where their involvement in various biological processes within the gastrointestinal tract has been posited. In this review, we summarize the molecular steps involved in eosinophil development and describe eosinophil trafficking to the gastrointestinal tract. We synthesize the current findings on the phenotypic and functional properties of gastrointestinal eosinophils and the accumulating evidence that they have a contributory role in gastrointestinal disorders, with a focus on primary eosinophilic gastrointestinal disorders. Finally, we discuss the potential role of eosinophils as modulators of the intestinal immune system. PMID:25049430

  17. Multiple lymphomatous polyposis of the gastrointestinal tract

    Directory of Open Access Journals (Sweden)

    Maria Isete Fares Franco

    Full Text Available CONTEXT: Gastrointestinal multiple lymphomatous polyposis is a rare type of malignant lymphoma that has aggressive biological behavior, early systemic dissemination and poor prognosis. It is considered to be a manifestation of non-Hodgkin lymphoma and represents the gastrointestinal counterpart of mantle cell nodal lymphoma. OBJECTIVE: A case of gastrointestinal multiple lymphomatous polyposis is presented and the anatomopathological, clinical, diagnostic and treatment aspects of this unusual neoplasia are discussed. CASE REPORT: The patient was a 59-year-old white male with a complaint of asthenia, night sweating, alteration in intestinal habit and weight loss over the preceding two months. The physical examination showed pallid mucosa and a palpable mass in the epigastrium and mesogastrium. Endoscopy of the upper digestive tract showed the presence of gastric and duodenal polyps. An opaque enema showed multiple polypoid lesions, especially in the cecum. A rectal biopsy revealed infiltration of the mucosa and submucosa by diffuse lymphoma consisting of small cleaved cells. Immunohistochemical study showed lymphocytes that expressed the antibody CD20 (L-26 and light-chain kappa (k immunoglobulin, but not light-chain lambda (l immunoglobulin. The patient presented a condition of acute intestinal obstruction with the presence of a mesenteric mass formed by agglutinated lymph nodes that surrounded the proximal ileum, thereby obstructing its lumen. He was submitted to a segmental enterectomy and gastrotomy with excisional biopsies of the gastric polypoid lesions. After two cycles of chemotherapy there was a worsening of the general state, with an increase in the dimensions of the abdominal masses and sepsis, accompanied by progressive respiratory insufficiency, leading to death.

  18. Relative importance of black carbon, brown carbon, and absorption enhancement from clear coatings in biomass burning emissions

    Science.gov (United States)

    Pokhrel, Rudra P.; Beamesderfer, Eric R.; Wagner, Nick L.; Langridge, Justin M.; Lack, Daniel A.; Jayarathne, Thilina; Stone, Elizabeth A.; Stockwell, Chelsea E.; Yokelson, Robert J.; Murphy, Shane M.

    2017-04-01

    A wide range of globally significant biomass fuels were burned during the fourth Fire Lab at Missoula Experiment (FLAME-4). A multi-channel photoacoustic absorption spectrometer (PAS) measured dry absorption at 405, 532, and 660 nm and thermally denuded (250 °C) absorption at 405 and 660 nm. Absorption coefficients were broken into contributions from black carbon (BC), brown carbon (BrC), and lensing following three different methodologies, with one extreme being a method that assumes the thermal denuder effectively removes organics and the other extreme being a method based on the assumption that black carbon (BC) has an Ångström exponent of unity. The methodologies employed provide ranges of potential importance of BrC to absorption but, on average, there was a difference of a factor of 2 in the ratio of the fraction of absorption attributable to BrC estimated by the two methods. BrC absorption at shorter visible wavelengths is of equal or greater importance to that of BC, with maximum contributions of up to 92 % of total aerosol absorption at 405 nm and up to 58 % of total absorption at 532 nm. Lensing is estimated to contribute a maximum of 30 % of total absorption, but typically contributes much less than this. Absorption enhancements and the estimated fraction of absorption from BrC show good correlation with the elemental-carbon-to-organic-carbon ratio (EC / OC) of emitted aerosols and weaker correlation with the modified combustion efficiency (MCE). Previous studies have shown that BrC grows darker (larger imaginary refractive index) as the ratio of black to organic aerosol (OA) mass increases. This study is consistent with those findings but also demonstrates that the fraction of total absorption attributable to BrC shows the opposite trend: increasing as the organic fraction of aerosol emissions increases and the EC / OC ratio decreases.

  19. Quantitation of small intestinal permeability during normal human drug absorption

    OpenAIRE

    Levitt, David G

    2013-01-01

    Background Understanding the quantitative relationship between a drug?s physical chemical properties and its rate of intestinal absorption (QSAR) is critical for selecting candidate drugs. Because of limited experimental human small intestinal permeability data, approximate surrogates such as the fraction absorbed or Caco-2 permeability are used, both of which have limitations. Methods Given the blood concentration following an oral and intravenous dose, the time course of intestinal absorpti...

  20. Endovascular treatment of nonvariceal acute arterial upper gastrointestinal bleeding

    DEFF Research Database (Denmark)

    Andersen, Poul Erik; Duvnjak, Stevo

    2010-01-01

    Transcatheter arterial embolization as treatment of upper nonvariceal gastrointestinal bleeding is increasingly being used after failed primary endoscopic treatment. The results after embolization have become better and surgery still has a high mortality. Embolization is a safe and effective...... procedure, but its use is has been limited because of relatively high rates of rebleeding and high mortality, both of which are associated with gastrointestinal bleeding and non-gastrointestinal related mortality causes. Transcatheter arterial embolization is a valuable minimal invasive method...